harmony 鸿蒙@ohos.data.distributedKVStore (Distributed KV Store)
@ohos.data.distributedKVStore (Distributed KV Store)
The distributedKVStore module implements collaboration between databases for different devices that forms a Super Device. You can use the APIs provided by this module to save application data to a distributed key-value (KV) store and perform operations, such as adding, deleting, modifying, querying, and synchronizing data in distributed KV stores.
The distributedKVStore module provides the following functions:
- KVManager: provides a KVManager instance to obtain KV store information.
- KVStoreResultSet: provides APIs for accessing the results obtained from a KV store.
- Query: provides APIs for setting predicates for data query.
- SingleKVStore: provides APIs for querying and synchronizing data in single KV stores. The single KV stores manage data without distinguishing devices.
- DeviceKVStore: provides APIs for querying and synchronizing data in device KV stores. This class inherits from SingleKVStore. The device KV stores manage data by device.
NOTE
The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
Modules to Import
import distributedKVStore from '@ohos.data.distributedKVStore';
KVManagerConfig
Provides the KVManager instance configuration, including the bundle name of the invoker and the application context.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Type | Mandatory | Description |
---|---|---|---|
context | Context | Yes | Application context. For details about the application context of the FA model, see Context. For details about the application context of the stage model, see Context. Since API version 10, the type of context is BaseContext. |
bundleName | string | Yes | Bundle name. |
Constants
Provides constants of the distributed KV store.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Value | Description |
---|---|---|
MAX_KEY_LENGTH | 1024 | Maximum length of a key in a distributed KV store, in bytes. |
MAX_VALUE_LENGTH | 4194303 | Maximum length of a value in a distributed KV store, in bytes. |
MAX_KEY_LENGTH_DEVICE | 896 | Maximum length of a key in a device KV store, in bytes. |
MAX_STORE_ID_LENGTH | 128 | Maximum length of a KV store ID, in bytes. |
MAX_QUERY_LENGTH | 512000 | Maximum query length, in bytes. |
MAX_BATCH_SIZE | 128 | Maximum number of batch operations. |
ValueType
Enumerates the types of the value in a KV pair.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Description |
---|---|
STRING | String. |
INTEGER | Integer. |
FLOAT | Float (single-precision floating point). |
BYTE_ARRAY | Byte array. |
BOOLEAN | Boolean. |
DOUBLE | Double (double-precision floating point). |
Value
Defines the value object in a KV store.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Type | Mandatory | Description |
---|---|---|---|
type | ValueType | Yes | Type of the value. |
value | Uint8Array |string |number |boolean | Yes | Value of the KV pair. |
Entry
Defines the KV pairs stored in a KV store.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of a KV pair in the KV store. |
value | Value | Yes | Value of a KV pair in the KV store. |
ChangeNotification
Defines the content of a data change notification, including inserted data, updated data, deleted data, and device ID.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Type | Mandatory | Description |
---|---|---|---|
insertEntries | Entry[] | Yes | Data inserted. |
updateEntries | Entry[] | Yes | Data updated. |
deleteEntries | Entry[] | Yes | Data deleted. |
deviceId | string | Yes | UUID of the device. |
SyncMode
Enumerates the synchronization modes.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Description |
---|---|
PULL_ONLY | Pull data from the peer end to the local end only. |
PUSH_ONLY | Push data from the local end to the peer end only. |
PUSH_PULL | Push data from the local end to the peer end and then pull data from the peer end to the local end. |
SubscribeType
Enumerates the subscription types.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Description |
---|---|
SUBSCRIBE_TYPE_LOCAL | Local data changes. |
SUBSCRIBE_TYPE_REMOTE | Remote data changes. |
SUBSCRIBE_TYPE_ALL | Local and remote data changes. |
KVStoreType
Enumerates the distributed KV store types.
Name | Description |
---|---|
DEVICE_COLLABORATION | Device KV store. The device KV store manages data by device, which eliminates conflicts. Data can be queried by device. System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore |
SINGLE_VERSION | Single KV store. The single KV store does not differentiate data by device. If entries with the same key are modified on different devices, the value will be overwritten. System capability: SystemCapability.DistributedDataManager.KVStore.Core |
SecurityLevel
Enumerates the KV store security levels.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Name | Description |
---|---|
S1 | Low security level. Disclosure, tampering, corruption, or loss of the data may cause minor impact on an individual or group. Examples: gender and nationality information, and user application records |
S2 | Medium security level. Disclosure, tampering, corruption, or loss of the data may cause major impact on an individual or group. Examples: mailing addresses and nicknames of individuals |
S3 | High security level. Disclosure, tampering, corruption, or loss of the data may cause critical impact on an individual or group. Examples: real-time precise positioning information and movement trajectory |
S4 | Critical security level. Disclosure, tampering, corruption, or loss of the data may cause significant adverse impact on an individual or group. Examples: political opinions, religious and philosophical belief, trade union membership, genetic data, biological information, health and sexual life status, sexual orientation, device authentication, and personal credit card information |
Options
Provides KV store configuration.
Name | Type | Mandatory | Description |
---|---|---|---|
createIfMissing | boolean | No | Whether to create a KV store if the database file does not exist. The default value is true, which means to create a KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core |
encrypt | boolean | No | Whether to encrypt the KV store. The default value is false, which means the KV store is not encrypted. System capability: SystemCapability.DistributedDataManager.KVStore.Core |
backup | boolean | No | Whether to back up the KV store. The default value is true, which means to back up the KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core |
autoSync | boolean | No | Whether to automatically synchronize database files. The default value is false, which means the database files are manually synchronized. System capability: SystemCapability.DistributedDataManager.KVStore.Core Required permissions: ohos.permission.DISTRIBUTED_DATASYNC |
kvStoreType | KVStoreType | No | Type of the KV store to create. The default value is DEVICE_COLLABORATION, which indicates a device KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core |
securityLevel | SecurityLevel | Yes | Security level of the KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core |
schema | Schema | No | Schema used to define the values stored in the KV store. The default value is undefined, which means no schema is used. System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore |
Schema
Defines the schema of a KV store. You can create a Schema object and place it in Options when creating or opening a KV store.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Name | Type | Readable | Writable | Description |
---|---|---|---|---|
root | FieldNode | Yes | Yes | JSON root object. |
indexes | Array<string> | Yes | Yes | String array in JSON format. |
mode | number | Yes | Yes | Schema mode. |
skip | number | Yes | Yes | Size of a skip of the schema. |
constructor
constructor()
A constructor used to create a Schema instance.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
FieldNode
Represents a Schema instance, which provides the methods for defining the values stored in a KV store.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Name | Type | Readable | Writable | Description |
---|---|---|---|---|
nullable | boolean | Yes | Yes | Whether the database field can be null. |
default | string | Yes | Yes | Default value of a FieldNode. |
type | number | Yes | Yes | Value of the data type corresponding to the specified node. |
constructor
constructor(name: string)
A constructor used to create a FieldNode instance with a string field.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
name | string | Yes | Value of FieldNode. |
appendChild
appendChild(child: FieldNode): boolean
Appends a child node to this FieldNode.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
child | FieldNode | Yes | Child node to append. |
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
try {
let node: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("root");
let child1: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("child1");
let child2: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("child2");
let child3: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("child3");
node.appendChild(child1);
node.appendChild(child2);
node.appendChild(child3);
console.info("appendNode " + JSON.stringify(node));
child1 = null;
child2 = null;
child3 = null;
node = null;
} catch (e) {
console.error("AppendChild " + e);
}
distributedKVStore.createKVManager
createKVManager(config: KVManagerConfig): KVManager
Creates a KVManager instance for KV store management.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
config | KVManagerConfig | Yes | KVManager instance configuration, including the bundle name and user information of the caller. |
Return value
Type | Description |
---|---|
KVManager | KVManager instance created. |
Example
Stage model:
import UIAbility from '@ohos.app.ability.UIAbility';
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager;
export default class EntryAbility extends UIAbility {
onCreate() {
console.info("MyAbilityStage onCreate")
let context = this.context
const kvManagerConfig: distributedKVStore.KVManagerConfig = {
context: context,
bundleName: 'com.example.datamanagertest',
}
try {
kvManager = distributedKVStore.createKVManager(kvManagerConfig);
console.info("Succeeded in creating KVManager");
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to create KVManager.code is ${error.code},message is ${error.message}`);
}
}
}
FA model:
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager;
let context = featureAbility.getContext()
const kvManagerConfig: distributedKVStore.KVManagerConfig = {
context: context,
bundleName: 'com.example.datamanagertest',
}
try {
kvManager = distributedKVStore.createKVManager(kvManagerConfig);
console.info("Succeeded in creating KVManager");
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to create KVManager.code is ${error.code},message is ${error.message}`);
}
KVManager
Provides an instance to obtain information about a distributed KV store. Before calling any API in KVManager, you must use createKVManager to create a KVManager instance.
getKVStore
getKVStore<T>(storeId: string, options: Options, callback: AsyncCallback<T>): void
Creates and obtains a distributed KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
storeId | string | Yes | Unique identifier of the KV store. The length cannot exceed MAX_STORE_ID_LENGTH. |
options | Options | Yes | Configuration of the KV store to create. |
callback | AsyncCallback<T> | Yes | Callback invoked to return the SingleKVStore or DeviceKVStore instance created. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100002 | Open existed database with changed options. |
15100003 | Database corrupted. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
try {
const options: distributedKVStore.Options = {
createIfMissing: true,
encrypt: false,
backup: false,
autoSync: true,
kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
securityLevel: distributedKVStore.SecurityLevel.S2,
};
kvManager.getKVStore('storeId', options, (err, store: distributedKVStore.SingleKVStore) => {
if (err) {
console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
return;
}
console.info("Succeeded in getting KVStore");
kvStore = store;
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
getKVStore
getKVStore<T>(storeId: string, options: Options): Promise<T>
Creates and obtains a distributed KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
storeId | string | Yes | Unique identifier of the KV store. The length cannot exceed MAX_STORE_ID_LENGTH. |
options | Options | Yes | Configuration of the distributed KV store to create. |
Return value
Type | Description |
---|---|
Promise<T> | Promise used to return the SingleKVStore or DeviceKVStore instance created. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100002 | Open existed database with changed options. |
15100003 | Database corrupted. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
try {
const options: distributedKVStore.Options = {
createIfMissing: true,
encrypt: false,
backup: false,
autoSync: true,
kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
securityLevel: distributedKVStore.SecurityLevel.S2,
};
kvManager.getKVStore<distributedKVStore.SingleKVStore>('storeId', options).then((store: distributedKVStore.SingleKVStore) => {
console.info("Succeeded in getting KVStore");
kvStore = store;
}).catch((err: BusinessError) => {
console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
closeKVStore
closeKVStore(appId: string, storeId: string, callback: AsyncCallback<void>): void
Closes a distributed KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
appId | string | Yes | Bundle name of the app that invokes the KV store. |
storeId | string | Yes | Unique identifier of the KV store to close. The length cannot exceed MAX_STORE_ID_LENGTH. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
const options: distributedKVStore.Options = {
createIfMissing: true,
encrypt: false,
backup: false,
autoSync: true,
kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
schema: undefined,
securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
kvManager.getKVStore('storeId', options, async (err, store: distributedKVStore.SingleKVStore|null) => {
if (err != undefined) {
console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting KVStore');
kvStore = store;
kvStore = null;
store = null;
kvManager.closeKVStore('appId', 'storeId', (err)=> {
if (err != undefined) {
console.error(`Failed to close KVStore.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing KVStore');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
closeKVStore
closeKVStore(appId: string, storeId: string): Promise<void>
Closes a distributed KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
appId | string | Yes | Bundle name of the app that invokes the KV store. |
storeId | string | Yes | Unique identifier of the KV store to close. The length cannot exceed MAX_STORE_ID_LENGTH. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
const options: distributedKVStore.Options = {
createIfMissing: true,
encrypt: false,
backup: false,
autoSync: true,
kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
schema: undefined,
securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
kvManager.getKVStore<distributedKVStore.SingleKVStore>('storeId', options).then(async (store: distributedKVStore.SingleKVStore|null) => {
console.info('Succeeded in getting KVStore');
kvStore = store;
kvStore = null;
store = null;
kvManager.closeKVStore('appId', 'storeId').then(() => {
console.info('Succeeded in closing KVStore');
}).catch((err: BusinessError) => {
console.error(`Failed to close KVStore.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to close KVStore.code is ${error.code},message is ${error.message}`);
}
deleteKVStore
deleteKVStore(appId: string, storeId: string, callback: AsyncCallback<void>): void
Deletes a distributed KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
appId | string | Yes | Bundle name of the app that invokes the KV store. |
storeId | string | Yes | Unique identifier of the KV store to delete. The length cannot exceed MAX_STORE_ID_LENGTH. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100004 | Not found. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
const options: distributedKVStore.Options = {
createIfMissing: true,
encrypt: false,
backup: false,
autoSync: true,
kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
schema: undefined,
securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
kvManager.getKVStore('store', options, async (err, store: distributedKVStore.SingleKVStore|null) => {
if (err != undefined) {
console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting KVStore');
kvStore = store;
kvStore = null;
store = null;
kvManager.deleteKVStore('appId', 'storeId', (err) => {
if (err != undefined) {
console.error(`Failed to delete KVStore.code is ${err.code},message is ${err.message}`);
return;
}
console.info(`Succeeded in deleting KVStore`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to delete KVStore.code is ${error.code},message is ${error.message}`);
}
deleteKVStore
deleteKVStore(appId: string, storeId: string): Promise<void>
Deletes a distributed KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
appId | string | Yes | Bundle name of the app that invokes the KV store. |
storeId | string | Yes | Unique identifier of the KV store to delete. The length cannot exceed MAX_STORE_ID_LENGTH. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100004 | Not found. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
const options: distributedKVStore.Options = {
createIfMissing: true,
encrypt: false,
backup: false,
autoSync: true,
kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
schema: undefined,
securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
kvManager.getKVStore<distributedKVStore.SingleKVStore>('storeId', options).then(async (store: distributedKVStore.SingleKVStore|null) => {
console.info('Succeeded in getting KVStore');
kvStore = store;
kvStore = null;
store = null;
kvManager.deleteKVStore('appId', 'storeId').then(() => {
console.info('Succeeded in deleting KVStore');
}).catch((err: BusinessError) => {
console.error(`Failed to delete KVStore.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to delete KVStore.code is ${error.code},message is ${error.message}`);
}
getAllKVStoreId
getAllKVStoreId(appId: string, callback: AsyncCallback<string[]>): void
Obtains the IDs of all distributed KV stores that are created by getKVStore and have not been deleted by deleteKVStore. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
appId | string | Yes | Bundle name of the app that invokes the KV store. |
callback | AsyncCallback<string[]> | Yes | Callback invoked to return the IDs of all the distributed KV stores created. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
try {
kvManager.getAllKVStoreId('appId', (err, data) => {
if (err != undefined) {
console.error(`Failed to get AllKVStoreId.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting AllKVStoreId');
console.info(`GetAllKVStoreId size = ${data.length}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get AllKVStoreId.code is ${error.code},message is ${error.message}`);
}
getAllKVStoreId
getAllKVStoreId(appId: string): Promise<string[]>
Obtains the IDs of all distributed KV stores that are created by getKVStore and have not been deleted by deleteKVStore. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
appId | string | Yes | Bundle name of the app that invokes the KV store. |
Return value
Type | Description |
---|---|
Promise<string[]> | Promise used to return the IDs of all the distributed KV stores created. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
try {
console.info('GetAllKVStoreId');
kvManager.getAllKVStoreId('appId').then((data: string[]) => {
console.info('Succeeded in getting AllKVStoreId');
console.info(`GetAllKVStoreId size = ${data.length}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get AllKVStoreId.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get AllKVStoreId.code is ${error.code},message is ${error.message}`);
}
on(‘distributedDataServiceDie’)
on(event: ‘distributedDataServiceDie’, deathCallback: Callback<void>): void
Subscribes to service status changes. If the service is terminated, you need to register the callbacks for data change notifications and synchronization complete notifications again. In addition, an error will be returned for a synchronization operation.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
event | string | Yes | Event to subscribe to. The value is distributedDataServiceDie, which indicates a service status change event. |
deathCallback | Callback<void> | Yes | Callback invoked to return service status changes. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
try {
console.info('KVManagerOn');
const deathCallback = () => {
console.info('death callback call');
}
kvManager.on('distributedDataServiceDie', deathCallback);
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
off(‘distributedDataServiceDie’)
off(event: ‘distributedDataServiceDie’, deathCallback?: Callback<void>): void
Unsubscribes from service status changes. The deathCallback parameter must be a callback registered for subscribing to service status changes. Otherwise, the unsubscription will fail.
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
event | string | Yes | Event to unsubscribe from. The value is distributedDataServiceDie, which indicates a service status change event. |
deathCallback | Callback<void> | No | Callback for the service status change event. If this parameter is not specified, all subscriptions to the service status change event will be canceled. |
Example
import { BusinessError } from '@ohos.base';
let kvManager: distributedKVStore.KVManager = xxx;
try {
console.info('KVManagerOff');
const deathCallback = () => {
console.info('death callback call');
}
kvManager.off('distributedDataServiceDie', deathCallback);
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
KVStoreResultSet
Provides APIs for obtaining the distributed KV store result sets. A maximum of eight result sets can be opened at a time.
Before calling any API in KVStoreResultSet, you must use getKVStore to construct a SingleKVStore or DeviceKVStore instance.
getCount
getCount(): number
Obtains the total number of rows in the result set.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
number | Total number of rows obtained. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let count: number;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
count = resultSet.getCount();
console.info("getCount succeed:" + count);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("getCount failed: " + e);
}
getPosition
getPosition(): number
Obtains the current data read position (position from which data is read) in the result set. The read position changes with the operations, such as moveToFirst and moveToLast.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
number | Current data read position obtained. The value must be greater than or equal to -1. The value -1 means no data is read; the value 0 indicates the first row. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let position: number;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeeded.');
resultSet = result;
position = resultSet.getPosition();
console.info("getPosition succeed:" + position);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("getPosition failed: " + e);
}
moveToFirst
moveToFirst(): boolean
Moves the data read position to the first row. If the result set is empty, false will be returned.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let moved: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
moved = resultSet.moveToFirst();
console.info("moveToFirst succeed: " + moved);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("moveToFirst failed " + e);
}
moveToLast
moveToLast(): boolean
Moves the data read position to the last row. If the result set is empty, false will be returned.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let moved: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
moved = resultSet.moveToLast();
console.info("moveToLast succeed:" + moved);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("moveToLast failed: " + e);
}
moveToNext
moveToNext(): boolean
Moves the data read position to the next row. If the result set is empty, false will be returned. This API applies when the whole result set is obtained.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let moved: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
do {
moved = resultSet.moveToNext();
const entry = resultSet.getEntry();
console.info("moveToNext succeed: " + moved);
} while (moved)
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("moveToNext failed: " + e);
}
moveToPrevious
moveToPrevious(): boolean
Moves the data read position to the previous row. If the result set is empty, false will be returned. This API applies when the whole result set is obtained.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let moved: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
moved = resultSet.moveToLast();
moved = resultSet.moveToPrevious();
console.info("moveToPrevious succeed:" + moved);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("moveToPrevious failed: " + e);
}
move
move(offset: number): boolean
Moves the data read position with the specified offset from the current position. That is, moves the number of rows specified by offset from the current position.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
offset | number | Yes | Offset to move the data read position. A negative value means to move backward, and a positive value means to move forward. |
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let moved: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('Succeeded in getting resultSet');
resultSet = result;
moved = resultSet.move(2); // If the current position is 0, move the read position forward by two rows, that is, move to row 3.
console.info(`Succeeded in moving.moved = ${moved}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to move.code is ${error.code},message is ${error.message}`);
}
moveToPosition
moveToPosition(position: number): boolean
Moves the data read position from 0 to an absolute position.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
position | number | Yes | Absolute position to move to. |
Return value
Type | Description |
---|---|
boolean | Returns true if the operation is successful; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let moved: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('Succeeded in getting resultSet');
resultSet = result;
moved = resultSet.moveToPosition(1);
console.info(`Succeeded in moving to position.moved=${moved}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to move to position.code is ${error.code},message is ${error.message}`);
}
isFirst
isFirst(): boolean
Checks whether the data read position is the first row.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the first row is being read; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let isfirst: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
isfirst = resultSet.isFirst();
console.info("Check isFirst succeed:" + isfirst);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("Check isFirst failed: " + e);
}
isLast
isLast(): boolean
Checks whether the data read position is the last row.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the last row is being read; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
let islast: boolean;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
islast = resultSet.isLast();
console.info("Check isLast succeed: " + islast);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("Check isLast failed: " + e);
}
isBeforeFirst
isBeforeFirst(): boolean
Checks whether the data read position is before the first row.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the data read position is before the first row; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
const isbeforefirst = resultSet.isBeforeFirst();
console.info("Check isBeforeFirst succeed: " + isbeforefirst);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("Check isBeforeFirst failed: " + e);
}
isAfterLast
isAfterLast(): boolean
Checks whether the data read position is after the last row.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
boolean | Returns true if the data read position is after the last row; returns false otherwise. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
const isafterlast = resultSet.isAfterLast();
console.info("Check isAfterLast succeed:" + isafterlast);
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("Check isAfterLast failed: " + e);
}
getEntry
getEntry(): Entry
Obtains the KV pair from the current position.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Entry | KV pair obtained. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet;
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('getResultSet succeed.');
resultSet = result;
const entry = resultSet.getEntry();
console.info("getEntry succeed:" + JSON.stringify(entry));
}).catch((err: BusinessError) => {
console.error('getResultSet failed: ' + err);
});
} catch (e) {
console.error("getEntry failed: " + e);
}
Query
Provides methods to create a Query object, which defines different data query criteria. A Query object supports a maximum of 256 predicates.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
constructor
constructor()
A constructor used to create a Schema instance.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
reset
reset(): Query
Resets the Query object.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Query | Query object reset. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.equalTo("key", "value");
console.info("query is " + query.getSqlLike());
query.reset();
console.info("query is " + query.getSqlLike());
query = null;
} catch (e) {
console.error("simply calls should be ok :" + e);
}
equalTo
equalTo(field: string, value: number|string|boolean): Query
Creates a Query object to match the specified field whose value is equal to the given value.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | number|string|boolean | Yes | Value specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.equalTo("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
notEqualTo
notEqualTo(field: string, value: number|string|boolean): Query
Creates a Query object to match the specified field whose value is not equal to the specified value.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | number|string|boolean | Yes | Value specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notEqualTo("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
greaterThan
greaterThan(field: string, value: number|string|boolean): Query
Creates a Query object to match the specified field whose value is greater than the specified value.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters |Name|Type|Mandatory|Description | |—–|——|—-|———————–| |fieId|string|Yes |Field to match. It cannot contain ‘^’.| |value|number|string|boolean|Yes |Value specified.|
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.greaterThan("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
lessThan
lessThan(field: string, value: number|string): Query
Creates a Query object to match the specified field whose value is less than the specified value.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | number|string | Yes | Value specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.lessThan("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
greaterThanOrEqualTo
greaterThanOrEqualTo(field: string, value: number|string): Query
Creates a Query object to match the specified field whose value is greater than or equal to the specified value.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | number|string | Yes | Value specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.greaterThanOrEqualTo("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
lessThanOrEqualTo
lessThanOrEqualTo(field: string, value: number|string): Query
Creates a Query object to match the specified field whose value is less than or equal to the specified value.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | number|string | Yes | Value specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.lessThanOrEqualTo("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
isNull
isNull(field: string): Query
Creates a Query object to match the specified field whose value is null.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.isNull("field");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
inNumber
inNumber(field: string, valueList: number[]): Query
Creates a Query object to match the specified field whose value is within the specified list of numbers.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
valueList | number[] | Yes | List of numbers. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.inNumber("field", [0, 1]);
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
inString
inString(field: string, valueList: string[]): Query
Creates a Query object to match the specified field whose value is within the specified list of strings.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
valueList | string[] | Yes | List of strings. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.inString("field", ['test1', 'test2']);
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
notInNumber
notInNumber(field: string, valueList: number[]): Query
Creates a Query object to match the specified field whose value is not within the specified list of numbers.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
valueList | number[] | Yes | List of numbers. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notInNumber("field", [0, 1]);
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
notInString
notInString(field: string, valueList: string[]): Query
Creates a Query object to match the specified field whose value is not within the specified list of strings.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
valueList | string[] | Yes | List of strings. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notInString("field", ['test1', 'test2']);
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
like
like(field: string, value: string): Query
Creates a Query object to match the specified field whose value is similar to the specified string.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | string | Yes | String specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.like("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
unlike
unlike(field: string, value: string): Query
Creates a Query object to match the specified field whose value is not similar to the specified string.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
value | string | Yes | String specified. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.unlike("field", "value");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
and
and(): Query
Creates a Query object with the AND condition.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notEqualTo("field", "value1");
query.and();
query.notEqualTo("field", "value2");
console.info("query is " + query.getSqlLike());
query = null;
} catch (e) {
console.error("duplicated calls should be ok :" + e);
}
or
or(): Query
Creates a Query object with the OR condition.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notEqualTo("field", "value1");
query.or();
query.notEqualTo("field", "value2");
console.info("query is " + query.getSqlLike());
query = null;
} catch (e) {
console.error("duplicated calls should be ok :" + e);
}
orderByAsc
orderByAsc(field: string): Query
Creates a Query object to sort the query results in ascending order.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notEqualTo("field", "value");
query.orderByAsc("field");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
orderByDesc
orderByDesc(field: string): Query
Creates a Query object to sort the query results in descending order.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notEqualTo("field", "value");
query.orderByDesc("field");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
limit
limit(total: number, offset: number): Query
Creates a Query object to specify the number of records of the query result and where to start. This API must be called after the invocation of the orderByAsc(), orderByDesc(), and the query APIs of the Query object.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
total | number | Yes | Number of results to query. |
offset | number | Yes | Start position for query. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
let total = 10;
let offset = 1;
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.notEqualTo("field", "value");
query.limit(total, offset);
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
isNotNull
isNotNull(field: string): Query
Creates a Query object to match the specified field whose value is not null.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
fieId | string | Yes | Field to match. It cannot contain ‘^’. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.isNotNull("field");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
beginGroup
beginGroup(): Query
Creates a Query object for a query condition group with a left parenthesis.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.beginGroup();
query.isNotNull("field");
query.endGroup();
console.info("query is " + query.getSqlLike());
query = null;
} catch (e) {
console.error("duplicated calls should be ok :" + e);
}
endGroup
endGroup(): Query
Creates a Query object for a query condition group with a right parenthesis.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.beginGroup();
query.isNotNull("field");
query.endGroup();
console.info("query is " + query.getSqlLike());
query = null;
} catch (e) {
console.error("duplicated calls should be ok :" + e);
}
prefixKey
prefixKey(prefix: string): Query
Creates a Query object with a specified key prefix.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
prefix | string | Yes | Key prefix. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.prefixKey("$.name");
query.prefixKey("0");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
setSuggestIndex
setSuggestIndex(index: string): Query
Creates a Query object with an index preferentially used for query.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
index | string | Yes | Index preferentially used for query. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.setSuggestIndex("$.name");
query.setSuggestIndex("0");
console.info(`query is ${query.getSqlLike()}`);
query = null;
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
deviceId
deviceId(deviceId:string):Query
Creates a Query object with the device ID as the key prefix. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | Device ID. |
Return value
Type | Description |
---|---|
Query | Query object created. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
query.deviceId("deviceId");
console.info(`query is ${query.getSqlLike()}`);
} catch (e) {
let error = e as BusinessError;
console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}
getSqlLike
getSqlLike():string
Obtains the query statement of the Query object.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
string | Returns the query statement obtained. |
Example
import { BusinessError } from '@ohos.base';
try {
let query: distributedKVStore.Query|null = new distributedKVStore.Query();
let sql1 = query.getSqlLike();
console.info(`GetSqlLike sql= ${sql1}`);
} catch (e) {
console.error("duplicated calls should be ok : " + e);
}
SingleKVStore
Implements data management in a single KV store, such as adding data, deleting data, and subscribing to data changes or data synchronization completion.
Before calling any method in SingleKVStore, you must use getKVStore to obtain a SingleKVStore instance.
put
put(key: string, value: Uint8Array|string|number|boolean, callback: AsyncCallback<void>): void
Adds a KV pair of the specified type to this KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the KV pair to add. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
value | Uint8Array |string |number |boolean | Yes | Value of the KV pair to add. The value type can be Uint8Array, number, string, or boolean. A value of the Uint8Array or string type cannot exceed MAX_VALUE_LENGTH. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
return;
}
console.info("Succeeded in putting");
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
put
put(key: string, value: Uint8Array|string|number|boolean): Promise<void>
Adds a KV pair of the specified type to this KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the KV pair to add. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
value | Uint8Array |string |number |boolean | Yes | Value of the KV pair to add. The value type can be Uint8Array, number, string, or boolean. A value of the Uint8Array or string type cannot exceed MAX_VALUE_LENGTH. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
console.info(`Succeeded in putting data`);
}).catch((err: BusinessError) => {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
putBatch
putBatch(entries: Entry[], callback: AsyncCallback<void>): void
Batch inserts KV pairs to this single KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
entries | Entry[] | Yes | KV pairs to insert in batches. An entries object allows a maximum of 128 entries. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting Batch');
kvStore.getEntries('batch_test_string_key', (err, entries) => {
if (err != undefined) {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
}
console.info('Succeeded in getting Entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}
putBatch
putBatch(entries: Entry[]): Promise<void>
Batch inserts KV pairs to this single KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
entries | Entry[] | Yes | KV pairs to insert in batches. An entries object allows a maximum of 128 entries. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting Batch');
kvStore.getEntries('batch_test_string_key').then((entries) => {
console.info('Succeeded in getting Entries');
console.info(`PutBatch ${entries}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}
putBatch
putBatch(value: Array<ValuesBucket>, callback: AsyncCallback<void>): void
Writes data to this single KV store. This API uses an asynchronous callback to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
value | Array<ValuesBucket> | Yes | Data to write. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let v8Arr: distributedKVStore.Entry[] = [];
let arr = new Uint8Array([4, 5, 6, 7]);
let vb1: distributedKVStore.Entry = { key: "name_1", value: 32 }
let vb2: distributedKVStore.Entry = { key: "name_2", value: arr };
let vb3: distributedKVStore.Entry = { key: "name_3", value: "lisi" };
v8Arr.push(vb1);
v8Arr.push(vb2);
v8Arr.push(vb3);
kvStore.putBatch(v8Arr, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
})
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to put batch.code is ${error.code},message is ${error.message}`);
}
putBatch
putBatch(value: Array<ValuesBucket>): Promise<void>
Write data to this KV store. This API uses a promise to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
value | Array<ValuesBucket> | Yes | Data to write. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let v8Arr: distributedKVStore.Entry[] = [];
let arr = new Uint8Array([4, 5, 6, 7]);
let vb1: distributedKVStore.Entry = { key: "name_1", value: 32 }
let vb2: distributedKVStore.Entry = { key: "name_2", value: arr };
let vb3: distributedKVStore.Entry = { key: "name_3", value: "lisi" };
v8Arr.push(vb1);
v8Arr.push(vb2);
v8Arr.push(vb3);
kvStore.putBatch(v8Arr).then(async () => {
console.info(`Succeeded in putting patch`);
}).catch((err: BusinessError) => {
console.error(`putBatch fail.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`putBatch fail.code is ${error.code},message is ${error.message}`);
}
delete
delete(key: string, callback: AsyncCallback<void>): void
Deletes a KV pair from this KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the KV pair to delete. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting');
kvStore.delete(KEY_TEST_STRING_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in deleting');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
delete
delete(key: string): Promise<void>
Deletes a KV pair from this KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the KV pair to delete. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
console.info(`Succeeded in putting data`);
kvStore.delete(KEY_TEST_STRING_ELEMENT).then(() => {
console.info('Succeeded in deleting');
}).catch((err: BusinessError) => {
console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
delete
delete(predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<void>)
Deletes KV pairs from this KV store. This API uses an asynchronous callback to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KV pairs to delete. If this parameter is null, define the processing logic. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let predicates = new dataSharePredicates.DataSharePredicates();
let arr = ["name"];
predicates.inKeys(arr);
kvStore.put("name", "bob", (err) => {
if (err != undefined) {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
return;
}
console.info("Succeeded in putting");
kvStore.delete(predicates, (err) => {
if (err == undefined) {
console.info('Succeeded in deleting');
} else {
console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
}
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
delete
delete(predicates: dataSharePredicates.DataSharePredicates): Promise<void>
Deletes KV pairs from this KV store. This API uses a promise to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KV pairs to delete. If this parameter is null, define the processing logic. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let predicates = new dataSharePredicates.DataSharePredicates();
let arr = ["name"];
predicates.inKeys(arr);
kvStore.put("name", "bob").then(() => {
console.info(`Succeeded in putting data`);
kvStore.delete(predicates).then(() => {
console.info('Succeeded in deleting');
}).catch((err: BusinessError) => {
console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
deleteBatch
deleteBatch(keys: string[], callback: AsyncCallback<void>): void
Batch deletes KV pairs from this single KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keys | string[] | Yes | KV pairs to delete in batches. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
let keys: string[] = [];
for (let i = 0; i < 5; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
keys.push(key + i);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting Batch');
kvStore.deleteBatch(keys, async (err) => {
if (err != undefined) {
console.error(`Failed to delete Batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in deleting Batch');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
deleteBatch
deleteBatch(keys: string[]): Promise<void>
Batch deletes KV pairs from this single KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keys | string[] | Yes | KV pairs to delete in batches. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
let keys: string[] = [];
for (let i = 0; i < 5; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
keys.push(key + i);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting Batch');
kvStore.deleteBatch(keys).then(() => {
console.info('Succeeded in deleting Batch');
}).catch((err: BusinessError) => {
console.error(`Failed to delete Batch.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
removeDeviceData
removeDeviceData(deviceId: string, callback: AsyncCallback<void>): void
Deletes data of a device. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-002';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, async (err) => {
console.info('Succeeded in putting data');
const deviceid = 'no_exist_device_id';
kvStore.removeDeviceData(deviceid, async (err) => {
if (err == undefined) {
console.info('succeeded in removing device data');
} else {
console.error(`Failed to remove device data.code is ${err.code},message is ${err.message} `);
kvStore.get(KEY_TEST_STRING_ELEMENT, async (err, data) => {
console.info('Succeeded in getting data');
});
}
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`)
}
removeDeviceData
removeDeviceData(deviceId: string): Promise<void>
Deletes data of a device. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-001';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
console.info('Succeeded in putting data');
}).catch((err: BusinessError) => {
console.error(`Failed to put data.code is ${err.code},message is ${err.message} `);
});
const deviceid = 'no_exist_device_id';
kvStore.removeDeviceData(deviceid).then(() => {
console.info('succeeded in removing device data');
}).catch((err: BusinessError) => {
console.error(`Failed to remove device data.code is ${err.code},message is ${err.message} `);
});
kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
console.info('Succeeded in getting data');
}).catch((err: BusinessError) => {
console.error(`Failed to get data.code is ${err.code},message is ${err.message} `);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`)
}
get
get(key: string, callback: AsyncCallback<boolean|string|number|Uint8Array>): void
Obtains the value of the specified key. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
callback | AsyncCallback<boolean |string |number |Uint8Array> | Yes | Callback invoked to return the value obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
return;
}
console.info("Succeeded in putting");
kvStore.get(KEY_TEST_STRING_ELEMENT, (err, data) => {
if (err != undefined) {
console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
return;
}
console.info(`Succeeded in getting data.data=${data}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}
get
get(key: string): Promise<boolean|string|number|Uint8Array>
Obtains the value of the specified key. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
Return value
Type | Description |
---|---|
Promise<Uint8Array |string |boolean |number> | Promise used to return the value obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
console.info(`Succeeded in putting data`);
kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
console.info(`Succeeded in getting data.data=${data}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(keyPrefix: string, callback: AsyncCallback<Entry[]>): void
Obtains all KV pairs that match the specified key prefix. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
callback | AsyncCallback<Entry[]> | Yes | Callback invoked to return the KV pairs that match the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting Batch');
kvStore.getEntries('batch_test_string_key', (err, entries) => {
if (err != undefined) {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting Entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}
getEntries
getEntries(keyPrefix: string): Promise<Entry[]>
Obtains all KV pairs that match the specified key prefix. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
Return value
Type | Description |
---|---|
Promise<Entry[]> | Promise used to return the KV pairs that match the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting Batch');
kvStore.getEntries('batch_test_string_key').then((entries) => {
console.info('Succeeded in getting Entries');
console.info(`PutBatch ${entries}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}
getEntries
getEntries(query: Query, callback: AsyncCallback<Entry[]>): void
Obtains the KV pairs that match the specified Query object. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Key prefix to match. |
callback | AsyncCallback<Entry[]> | Yes | Callback invoked to return the KV pairs that match the specified Query object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let arr = new Uint8Array([21, 31]);
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_bool_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.BYTE_ARRAY,
value: arr
}
}
entries.push(entry);
}
console.info(`entries: {entries}`);
kvStore.putBatch(entries, async (err) => {
console.info('Succeeded in putting Batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getEntries(query, (err, entries) => {
if (err != undefined) {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting Entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(query: Query): Promise<Entry[]>
Obtains the KV pairs that match the specified Query object. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<Entry[]> | Promise used to return the KV pairs that match the specified Query object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let arr = new Uint8Array([21, 31]);
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_bool_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.BYTE_ARRAY,
value: arr
}
}
entries.push(entry);
}
console.info(`entries: {entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting Batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getEntries(query).then((entries) => {
console.info('Succeeded in getting Entries');
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`)
});
console.info('Succeeded in getting Entries');
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(keyPrefix: string, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a result set with the specified prefix from this single KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the result set with the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
kvStore.getResultSet('batch_test_string_key', async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing result set');
})
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(keyPrefix: string): Promise<KVStoreResultSet>
Obtains a result set with the specified prefix from this single KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise used to return the result set with the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing result set');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(query: Query, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified Query object. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSet(query, async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(query: Query): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified Query object. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise used to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSet(query).then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified predicate object. This API uses an asynchronous callback to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let predicates = new dataSharePredicates.DataSharePredicates();
predicates.prefixKey("batch_test_string_key");
kvStore.getResultSet(predicates, async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing result set');
})
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(predicates: dataSharePredicates.DataSharePredicates): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified predicate object. This API uses a promise to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let predicates = new dataSharePredicates.DataSharePredicates();
predicates.prefixKey("batch_test_string_key");
kvStore.getResultSet(predicates).then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing result set');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
closeResultSet
closeResultSet(resultSet: KVStoreResultSet, callback: AsyncCallback<void>): void
Closes the KVStoreResultSet object returned by SingleKvStore.getResultSet. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
resultSet | KVStoreResultSet | Yes | KVStoreResultSet object to close. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
kvStore.closeResultSet(resultSet, (err) => {
if (err == undefined) {
console.info('Succeeded in closing result set');
} else {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
closeResultSet
closeResultSet(resultSet: KVStoreResultSet): Promise<void>
Closes the KVStoreResultSet object returned by SingleKvStore.getResultSet. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
resultSet | KVStoreResultSet | Yes | KVStoreResultSet object to close. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing result set');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSize
getResultSize(query: Query, callback: AsyncCallback<number>): void
Obtains the number of results that matches the specified Query object. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
callback | AsyncCallback<number> | Yes | Callback invoked to return the number of results obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
console.info('Succeeded in putting batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSize(query, async (err, resultSize) => {
if (err != undefined) {
console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set size');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSize
getResultSize(query: Query): Promise<number>
Obtains the number of results that matches the specified Query object. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<number> | Promise used to return the number of results obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSize(query).then((resultSize) => {
console.info('Succeeded in getting result set size');
}).catch((err: BusinessError) => {
console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
backup
backup(file:string, callback: AsyncCallback<void>):void
Backs up a distributed KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
file | string | Yes | Name of the KV store. The value cannot be empty or exceed MAX_KEY_LENGTH. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. If the operation is successful, err is undefined. Otherwise, err is an error object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let file = "BK001";
try {
kvStore.backup(file, (err) => {
if (err) {
console.error(`Failed to backup.code is ${err.code},message is ${err.message} `);
} else {
console.info(`Succeeded in backupping data`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
backup
backup(file:string): Promise<void>
Backs up an RDB store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
file | string | Yes | Name of the KV store. The value cannot be empty or exceed MAX_KEY_LENGTH. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let file = "BK001";
try {
kvStore.backup(file).then(() => {
console.info(`Succeeded in backupping data`);
}).catch((err: BusinessError) => {
console.error(`Failed to backup.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
restore
restore(file:string, callback: AsyncCallback<void>):void
Restores a distributed KV store from a database file. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
file | string | Yes | Name of the database file. The value cannot be empty or exceed MAX_KEY_LENGTH. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. If the operation is successful, err is undefined. Otherwise, err is an error object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let file = "BK001";
try {
kvStore.restore(file, (err) => {
if (err) {
console.error(`Failed to restore.code is ${err.code},message is ${err.message}`);
} else {
console.info(`Succeeded in restoring data`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
restore
restore(file:string): Promise<void>
Restores a distributed KV store from a database file. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
file | string | Yes | Name of the database file. The value cannot be empty or exceed MAX_KEY_LENGTH. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let file = "BK001";
try {
kvStore.restore(file).then(() => {
console.info(`Succeeded in restoring data`);
}).catch((err: BusinessError) => {
console.error(`Failed to restore.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
deleteBackup
deleteBackup(files:Array<string>, callback: AsyncCallback<Array<[string, number]>>):void
Deletes a backup file. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
files | Array<string> | Yes | Name of the backup file to delete. The value cannot be empty or exceed MAX_KEY_LENGTH. |
callback | AsyncCallback<Array<[string, number]>> | Yes | Callback invoked to return the name of the backup file deleted and the operation result. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let files = ["BK001", "BK002"];
try {
kvStore.deleteBackup(files, (err, data) => {
if (err) {
console.error(`Failed to delete Backup.code is ${err.code},message is ${err.message}`);
} else {
console.info(`Succeed in deleting Backup.data=${data}`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
deleteBackup
deleteBackup(files:Array<string>): Promise<Array<[string, number]>>
Deletes a backup file. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
files | Array<string> | Yes | Name of the backup file to delete. The value cannot be empty or exceed MAX_KEY_LENGTH. |
Return value
Type | Description |
---|---|
Promise<Array<[string, number]>> | Promise used to return the name of the backup file deleted and the operation result. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let files = ["BK001", "BK002"];
try {
kvStore.deleteBackup(files).then((data) => {
console.info(`Succeed in deleting Backup.data=${data}`);
}).catch((err: BusinessError) => {
console.error(`Failed to delete Backup.code is ${err.code},message is ${err.message}`);
})
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
startTransaction
startTransaction(callback: AsyncCallback<void>): void
Starts the transaction in this single KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
function putBatchString(len: number, prefix: string) {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < len; i++) {
let entry: distributedKVStore.Entry = {
key: prefix + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
return entries;
}
try {
let count = 0;
kvStore.on('dataChange', 0, (data) => {
console.info(`startTransaction 0 ${data}`);
count++;
});
kvStore.startTransaction(async (err) => {
if (err != undefined) {
console.error(`Failed to start Transaction.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in starting Transaction');
let entries = putBatchString(10, 'batch_test_string_key');
console.info(`entries: ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting Batch');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to start Transaction.code is ${error.code},message is ${error.message}`);
}
startTransaction
startTransaction(): Promise<void>
Starts the transaction in this single KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
For details about the error codes, see RDB Error Codes.
ID | Error Message |
---|---|
14800047 | The WAL file size exceeds the default limit. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
let count = 0;
kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_ALL, (data) => {
console.info(`startTransaction 0 ${data}`);
count++;
});
kvStore.startTransaction().then(async () => {
console.info('Succeeded in starting Transaction');
}).catch((err: BusinessError) => {
console.error(`Failed to start Transaction.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to start Transaction.code is ${error.code},message is ${error.message}`);
}
commit
commit(callback: AsyncCallback<void>): void
Commits the transaction in this single KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.commit((err) => {
if (err == undefined) {
console.info('Succeeded in committing');
} else {
console.error(`Failed to commit.code is ${err.code},message is ${err.message}`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
commit
commit(): Promise<void>
Commits the transaction in this single KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.commit().then(async () => {
console.info('Succeeded in committing');
}).catch((err: BusinessError) => {
console.error(`Failed to commit.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
rollback
rollback(callback: AsyncCallback<void>): void
Rolls back the transaction in this single KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.rollback((err) => {
if (err == undefined) {
console.info('Succeeded in rolling back');
} else {
console.error(`Failed to rollback.code is ${err.code},message is ${err.message}`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
rollback
rollback(): Promise<void>
Rolls back the transaction in this single KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.rollback().then(async () => {
console.info('Succeeded in rolling back');
}).catch((err: BusinessError) => {
console.error(`Failed to rollback.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
enableSync
enableSync(enabled: boolean, callback: AsyncCallback<void>): void
Sets data synchronization, which can be enabled or disabled. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
enabled | boolean | Yes | Whether to enable data synchronization. The value true means to enable data synchronization, and false means the opposite. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.enableSync(true, (err) => {
if (err == undefined) {
console.info('Succeeded in enabling sync');
} else {
console.error(`Failed to enable sync.code is ${err.code},message is ${err.message}`);
}
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
enableSync
enableSync(enabled: boolean): Promise<void>
Sets data synchronization, which can be enabled or disabled. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
enabled | boolean | Yes | Whether to enable data synchronization. The value true means to enable data synchronization, and false means the opposite. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.enableSync(true).then(() => {
console.info('Succeeded in enabling sync');
}).catch((err: BusinessError) => {
console.error(`Failed to enable sync.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
setSyncRange
setSyncRange(localLabels: string[], remoteSupportLabels: string[], callback: AsyncCallback<void>): void
Sets the data synchronization range. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
localLabels | string[] | Yes | Synchronization labels set for the local device. |
remoteSupportLabels | string[] | Yes | Synchronization labels set for remote devices. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
const localLabels = ['A', 'B'];
const remoteSupportLabels = ['C', 'D'];
kvStore.setSyncRange(localLabels, remoteSupportLabels, (err) => {
if (err != undefined) {
console.error(`Failed to set syncRange.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in setting syncRange');
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
setSyncRange
setSyncRange(localLabels: string[], remoteSupportLabels: string[]): Promise<void>
Sets the data synchronization range. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
localLabels | string[] | Yes | Synchronization labels set for the local device. |
remoteSupportLabels | string[] | Yes | Synchronization labels set for remote devices. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
const localLabels = ['A', 'B'];
const remoteSupportLabels = ['C', 'D'];
kvStore.setSyncRange(localLabels, remoteSupportLabels).then(() => {
console.info('Succeeded in setting syncRange');
}).catch((err: BusinessError) => {
console.error(`Failed to set syncRange.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
setSyncParam
setSyncParam(defaultAllowedDelayMs: number, callback: AsyncCallback<void>): void
Sets the default delay allowed for KV store synchronization. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
defaultAllowedDelayMs | number | Yes | Default delay allowed for database synchronization, in ms. |
callback | AsyncCallback<void> | Yes | Callback invoked to return the result. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
const defaultAllowedDelayMs = 500;
kvStore.setSyncParam(defaultAllowedDelayMs, (err) => {
if (err != undefined) {
console.error(`Failed to set syncParam.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in setting syncParam');
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
setSyncParam
setSyncParam(defaultAllowedDelayMs: number): Promise<void>
Sets the default delay allowed for KV store synchronization. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
defaultAllowedDelayMs | number | Yes | Default delay allowed for database synchronization, in ms. |
Return value
Type | Description |
---|---|
Promise<void> | Promise that returns no value. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
const defaultAllowedDelayMs = 500;
kvStore.setSyncParam(defaultAllowedDelayMs).then(() => {
console.info('Succeeded in setting syncParam');
}).catch((err: BusinessError) => {
console.error(`Failed to set syncParam.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
sync
sync(deviceIds: string[], mode: SyncMode, delayMs?: number): void
Synchronizes the KV store manually. For details about the synchronization modes of KV stores, see Cross-Device Synchronization of KV Stores. > NOTE > > deviceIds is networkId in DeviceBasicInfo, which can be obtained by deviceManager.getAvailableDeviceListSync.
Required permissions: ohos.permission.DISTRIBUTED_DATASYNC
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceIds | string[] | Yes | List of networkIds of the devices in the same networking environment to be synchronized. |
mode | SyncMode | Yes | Synchronization mode. |
delayMs | number | No | Allowed synchronization delay time, in ms. The default value is 0. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
Example
import deviceManager from '@ohos.distributedDeviceManager';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let devManager: deviceManager.DeviceManager;
const KEY_TEST_SYNC_ELEMENT = 'key_test_sync';
const VALUE_TEST_SYNC_ELEMENT = 'value-string-001';
// create deviceManager
try {
devManager = deviceManager.createDeviceManager(context.applicationInfo.name);
let deviceIds: string[] = [];
if (devManager != null) {
let devices = devManager.getAvailableDeviceListSync();
for (let i = 0; i < devices.length; i++) {
deviceIds[i] = devices[i].networkId as string;
}
}
try {
kvStore.on('syncComplete', (data) => {
console.info('Sync dataChange');
});
kvStore.put(KEY_TEST_SYNC_ELEMENT + 'testSync101', VALUE_TEST_SYNC_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to sync.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting data');
const mode = distributedKVStore.SyncMode.PULL_ONLY;
kvStore.sync(deviceIds, mode, 1000);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to sync.code is ${error.code},message is ${error.message}`);
}
} catch (err) {
let error = err as BusinessError;
console.error("createDeviceManager errCode:" + error.code + ",errMessage:" + error.message);
}
sync
sync(deviceIds: string[], query: Query, mode: SyncMode, delayMs?: number): void
Synchronizes the KV store manually. This API returns the result synchronously. For details about the synchronization modes of KV stores, see Cross-Device Synchronization of KV Stores. > NOTE > > deviceIds is networkId in DeviceBasicInfo, which can be obtained by deviceManager.getAvailableDeviceListSync.
Required permissions: ohos.permission.DISTRIBUTED_DATASYNC
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceIds | string[] | Yes | List of networkIds of the devices in the same networking environment to be synchronized. |
mode | SyncMode | Yes | Synchronization mode. |
query | Query | Yes | Query object to match. |
delayMs | number | No | Allowed synchronization delay time, in ms. The default value is 0. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
Example
import deviceManager from '@ohos.distributedDeviceManager';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
let devManager: deviceManager.DeviceManager;
const KEY_TEST_SYNC_ELEMENT = 'key_test_sync';
const VALUE_TEST_SYNC_ELEMENT = 'value-string-001';
// create deviceManager
try {
let devManager = deviceManager.createDeviceManager(context.applicationInfo.name);
let deviceIds: string[] = [];
if (devManager != null) {
let devices = devManager.getAvailableDeviceListSync();
for (let i = 0; i < devices.length; i++) {
deviceIds[i] = devices[i].networkId as string;
}
}
try {
kvStore.on('syncComplete', (data) => {
console.info('Sync dataChange');
});
kvStore.put(KEY_TEST_SYNC_ELEMENT + 'testSync101', VALUE_TEST_SYNC_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to sync.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting data');
const mode = distributedKVStore.SyncMode.PULL_ONLY;
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
query.deviceId(devManager.getLocalDeviceNetworkId());
kvStore.sync(deviceIds, query, mode, 1000);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to sync.code is ${error.code},message is ${error.message}`);
}
} catch (err) {
let error = err as BusinessError;
console.error("createDeviceManager errCode:" + error.code + ",errMessage:" + error.message);
}
on(‘dataChange’)
on(event: ‘dataChange’, type: SubscribeType, listener: Callback<ChangeNotification>): void
Subscribes to data changes of the specified type.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
event | string | Yes | Event type. The value is dataChange, which indicates data changes. |
type | SubscribeType | Yes | Type of data change. |
listener | Callback<ChangeNotification> | Yes | Callback invoked to return the data change. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_LOCAL, (data) => {
console.info(`dataChange callback call data: ${data}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
on(‘syncComplete’)
on(event: ‘syncComplete’, syncCallback: Callback<Array<[string, number]>>): void
Subscribes to synchronization complete events.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
event | string | Yes | Event type. The value is syncComplete, which indicates a synchronization complete event. |
syncCallback | Callback<Array<[string, number]>> | Yes | Callback invoked to return the synchronization complete event. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_FLOAT_ELEMENT = 'key_test_float';
const VALUE_TEST_FLOAT_ELEMENT = 321.12;
try {
kvStore.on('syncComplete', (data) => {
console.info(`syncComplete ${data}`);
});
kvStore.put(KEY_TEST_FLOAT_ELEMENT, VALUE_TEST_FLOAT_ELEMENT).then(() => {
console.info('succeeded in putting');
}).catch((err: BusinessError) => {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to subscribe syncComplete.code is ${error.code},message is ${error.message}`);
}
off(‘dataChange’)
off(event:‘dataChange’, listener?: Callback<ChangeNotification>): void
Unsubscribes from data changes.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
event | string | Yes | Event type. The value is dataChange, which indicates data changes. |
listener | Callback<ChangeNotification> | No | Callback for the data change. If the callback is not specified, all callbacks for dataChange will be unregistered. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
class KvstoreModel {
call(data: string) {
console.info(`dataChange : ${data}`);
}
subscribeDataChange() {
try {
if (kvStore != null) {
kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_REMOTE, this.call);
}
} catch (err) {
let error = err as BusinessError;
console.error(`Failed to subscribeDataChange.code is ${error.code},message is ${error.message}`);
}
}
unsubscribeDataChange() {
try {
if (kvStore != null) {
kvStore.off('dataChange', this.call);
}
} catch (err) {
let error = err as BusinessError;
console.error(`Failed to unsubscribeDataChange.code is ${error.code},message is ${error.message}`);
}
}
}
off(‘syncComplete’)
off(event: ‘syncComplete’, syncCallback?: Callback<Array<[string, number]>>): void
Unsubscribes from synchronization complete events.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
event | string | Yes | Event type. The value is syncComplete, which indicates a synchronization complete event. |
syncCallback | Callback<Array<[string, number]>> | No | Callback for the synchronization complete event. If the callback is not specified, all callbacks for syncComplete will be unregistered. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
class KvstoreModel {
call(data: string) {
console.info(`syncComplete : ${data}`);
}
subscribeDataChange() {
try {
if (kvStore != null) {
kvStore.on('syncComplete', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_REMOTE, this.call);
}
} catch (err) {
let error = err as BusinessError;
console.error(`Failed to subscribeDataChange.code is ${error.code},message is ${error.message}`);
}
}
unsubscribeDataChange() {
try {
if (kvStore != null) {
kvStore.off('dsyncComplete', this.call);
}
} catch (err) {
let error = err as BusinessError;
console.error(`Failed to unsubscribeDataChange.code is ${error.code},message is ${error.message}`);
}
}
}
getSecurityLevel
getSecurityLevel(callback: AsyncCallback<SecurityLevel>): void
Obtains the security level of this KV store. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
callback | AsyncCallback<SecurityLevel> | Yes | Callback invoked to return the security level obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.getSecurityLevel((err, data) => {
if (err != undefined) {
console.error(`Failed to get SecurityLevel.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting securityLevel');
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
getSecurityLevel
getSecurityLevel(): Promise<SecurityLevel>
Obtains the security level of this KV store. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Return value
Type | Description |
---|---|
Promise<SecurityLevel> | Promise used to return the security level obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
kvStore.getSecurityLevel().then((data) => {
console.info('Succeeded in getting securityLevel');
}).catch((err: BusinessError) => {
console.error(`Failed to get SecurityLevel.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
DeviceKVStore
Provides APIs for querying and synchronizing data in a device KV store. This class inherits from SingleKVStore.
Data is distinguished by device in a device KV store. Each device can only write and modify its own data. Data of other devices is read-only and cannot be modified.
For example, a device KV store can be used to implement image sharing between devices. The images of other devices can be viewed, but not be modified or deleted.
Before calling any method in DeviceKVStore, you must use getKVStore to obtain a DeviceKVStore object.
get
get(key: string, callback: AsyncCallback<boolean|string|number|Uint8Array>): void
Obtains the value of the specified key for this device. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
callback | AsyncCallback<boolean |string |number |Uint8Array> | Yes | Callback invoked to return the value obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
if (err != undefined) {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
return;
}
console.info("Succeeded in putting");
kvStore.get(KEY_TEST_STRING_ELEMENT, (err, data) => {
if (err != undefined) {
console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
return;
}
console.info(`Succeeded in getting data.data=${data}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}
get
get(key: string): Promise<boolean|string|number|Uint8Array>
Obtains the value of the specified key for this device. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
key | string | Yes | Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH. |
Return value
Type | Description |
---|---|
Promise<Uint8Array |string |boolean |number> | Promise used to return the value obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
console.info(`Succeeded in putting data`);
kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
console.info(`Succeeded in getting data.data=${data}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}
get
get(deviceId: string, key: string, callback: AsyncCallback<boolean|string|number|Uint8Array>): void
Obtains a string value that matches the specified device ID and key. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
key | string | Yes | Key to match. |
callback | AsyncCallback<boolean|string|number|Uint8Array> | Yes | Callback invoked to return the value obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-002';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, async (err) => {
if (err != undefined) {
console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting');
kvStore.get('localDeviceId', KEY_TEST_STRING_ELEMENT, (err, data) => {
if (err != undefined) {
console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting');
});
})
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}
get
get(deviceId: string, key: string): Promise<boolean|string|number|Uint8Array>
Obtains a string value that matches the specified device ID and key. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
key | string | Yes | Key to match. |
Return value
Type | Description |
---|---|
Promise<boolean|string|number|Uint8Array> | Promise used to return the string value that matches the given condition. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100004 | Not found. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-002';
try {
kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(async () => {
console.info('Succeeded in putting');
kvStore.get('localDeviceId', KEY_TEST_STRING_ELEMENT).then((data) => {
console.info('Succeeded in getting');
}).catch((err: BusinessError) => {
console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
});
}).catch((error: BusinessError) => {
console.error(`Failed to put.code is ${error.code},message is ${error.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(keyPrefix: string, callback: AsyncCallback<Entry[]>): void
Obtains all KV pairs that match the specified key prefix for this device. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
callback | AsyncCallback<Entry[]> | Yes | Callback invoked to return the KV pairs that match the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting Batch');
kvStore.getEntries('batch_test_string_key', (err, entries) => {
if (err != undefined) {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting Entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}
getEntries
getEntries(keyPrefix: string): Promise<Entry[]>
Obtains all KV pairs that match the specified key prefix for this device. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
Return value
Type | Description |
---|---|
Promise<Entry[]> | Promise used to return the KV pairs that match the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting Batch');
kvStore.getEntries('batch_test_string_key').then((entries) => {
console.info('Succeeded in getting Entries');
console.info(`PutBatch ${entries}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}
getEntries
getEntries(deviceId: string, keyPrefix: string, callback: AsyncCallback<Entry[]>): void
Obtains all KV pairs that match the specified device ID and key prefix. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
keyPrefix | string | Yes | Key prefix to match. |
callback | AsyncCallback<Entry[]> | Yes | Callback invoked to return the KV pairs obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries : ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
kvStore.getEntries('localDeviceId', 'batch_test_string_key', (err, entries) => {
if (err != undefined) {
console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to put batch.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(deviceId: string, keyPrefix: string): Promise<Entry[]>
Obtains all KV pairs that match the specified device ID and key prefix. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
keyPrefix | string | Yes | Key prefix to match. |
Return value
Type | Description |
---|---|
Promise<Entry[]> | Promise used to return all the KV pairs that match the given condition. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
kvStore.getEntries('localDeviceId', 'batch_test_string_key').then((entries) => {
console.info('Succeeded in getting entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
console.info(`entries[0].value: ${entries[0].value}`);
console.info(`entries[0].value.value: ${entries[0].value.value}`);
}).catch((err: BusinessError) => {
console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to put batch.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(query: Query, callback: AsyncCallback<Entry[]>): void
Obtains all KV pairs that match the specified Query object for this device. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Key prefix to match. |
callback | AsyncCallback<Entry[]> | Yes | Callback invoked to return the KV pairs that match the specified Query object on the local device. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let arr = new Uint8Array([21, 31]);
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_bool_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.BYTE_ARRAY,
value: arr
}
}
entries.push(entry);
}
console.info(`entries: {entries}`);
kvStore.putBatch(entries, async (err) => {
console.info('Succeeded in putting Batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getEntries(query, (err, entries) => {
if (err != undefined) {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting Entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(query: Query): Promise<Entry[]>
Obtains all KV pairs that match the specified Query object for this device. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<Entry[]> | Promise used to return the KV pairs that match the specified Query object on the local device. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let arr = new Uint8Array([21, 31]);
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_bool_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.BYTE_ARRAY,
value: arr
}
}
entries.push(entry);
}
console.info(`entries: {entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting Batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getEntries(query).then((entries) => {
console.info('Succeeded in getting Entries');
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`)
});
console.info('Succeeded in getting Entries');
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(deviceId: string, query: Query, callback: AsyncCallback<Entry[]>): void
Obtains the KV pairs that match the specified device ID and Query object. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
query | Query | Yes | Query object to match. |
callback | AsyncCallback<Entry[]> | Yes | Callback invoked to return the KV pairs that match the specified device ID and Query object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let arr = new Uint8Array([21, 31]);
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_bool_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.BYTE_ARRAY,
value: arr
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
let query = new distributedKVStore.Query();
query.deviceId('localDeviceId');
query.prefixKey("batch_test");
kvStore.getEntries('localDeviceId', query, (err, entries) => {
if (err != undefined) {
console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting entries');
console.info(`entries.length: ${entries.length}`);
console.info(`entries[0]: ${entries[0]}`);
})
});
console.info('Succeeded in getting entries');
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get entries.code is ${error.code},message is ${error.message}`);
}
getEntries
getEntries(deviceId: string, query: Query): Promise<Entry[]>
Obtains the KV pairs that match the specified device ID and Query object. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<Entry[]> | Promise used to return the KV pairs that match the specified device ID and Query object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let arr = new Uint8Array([21, 31]);
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_bool_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.BYTE_ARRAY,
value: arr
}
}
entries.push(entry);
}
console.info(`entries: ${entries}`);
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
let query = new distributedKVStore.Query();
query.deviceId('localDeviceId');
query.prefixKey("batch_test");
kvStore.getEntries('localDeviceId', query).then((entries) => {
console.info('Succeeded in getting entries');
}).catch((err: BusinessError) => {
console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
});
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
console.info('Succeeded in getting entries');
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get entries.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(keyPrefix: string, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a result set with the specified prefix for this device. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the result set with the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
kvStore.getResultSet('batch_test_string_key', async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing result set');
})
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(keyPrefix: string): Promise<KVStoreResultSet>
Obtains a result set with the specified prefix for this device. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
keyPrefix | string | Yes | Key prefix to match. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise used to return the result set with the specified prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
kvStore.getResultSet('batch_test_string_key').then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing result set');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(deviceId: string, keyPrefix: string, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified device ID and key prefix. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
keyPrefix | string | Yes | Key prefix to match. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object that matches the specified device ID and key prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
kvStore.getResultSet('localDeviceId', 'batch_test_string_key', async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting resultSet');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing resultSet');
})
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(deviceId: string, keyPrefix: string): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified device ID and key prefix. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
keyPrefix | string | Yes | Key prefix to match. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise used to return the KVStoreResultSet object that matches the specified device ID and key prefix. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
kvStore.getResultSet('localDeviceId', 'batch_test_string_key').then((result) => {
console.info('Succeeded in getting resultSet');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
});
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing resultSet');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(deviceId: string, query: Query, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified device ID and Query object. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the device to which the KVStoreResultSet object belongs. |
query | Query | Yes | Query object to match. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object that matches the specified device ID and Query object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSet('localDeviceId', query, async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting resultSet');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing resultSet');
})
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(deviceId: string, query: Query): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified device ID and Query object. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the device to which the KVStoreResultSet object belongs. |
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise used to return the KVStoreResultSet object that matches the specified device ID and Query object. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSet('localDeviceId', query).then((result) => {
console.info('Succeeded in getting resultSet');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
});
query.deviceId('localDeviceId');
console.info("GetResultSet " + query.getSqlLike());
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing resultSet');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(query: Query): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified Query object for this device. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise used to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSet(query).then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(query: Query, callback:AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified Query object for this device. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSet(query, async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting resultSet');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing resultSet');
})
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}
getResultSet
getResultSet(predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified predicate object for this device. This API uses an asynchronous callback to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let predicates = new dataSharePredicates.DataSharePredicates();
predicates.prefixKey("batch_test_string_key");
kvStore.getResultSet(predicates, async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing result set');
})
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(predicates: dataSharePredicates.DataSharePredicates): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified predicate object for this device. This API uses a promise to return the result.
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let predicates = new dataSharePredicates.DataSharePredicates();
predicates.prefixKey("batch_test_string_key");
kvStore.getResultSet(predicates).then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing result set');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(deviceId: string, predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<KVStoreResultSet>): void
Obtains a KVStoreResultSet object that matches the specified predicate object and device ID. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic. |
callback | AsyncCallback<KVStoreResultSet> | Yes | Callback invoked to return the KVStoreResultSet object obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let predicates = new dataSharePredicates.DataSharePredicates();
predicates.prefixKey("batch_test_string_key");
kvStore.getResultSet('localDeviceId', predicates, async (err, result) => {
if (err != undefined) {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set');
resultSet = result;
kvStore.closeResultSet(resultSet, (err) => {
if (err != undefined) {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in closing result set');
})
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSet
getResultSet(deviceId: string, predicates: dataSharePredicates.DataSharePredicates): Promise<KVStoreResultSet>
Obtains a KVStoreResultSet object that matches the specified predicate object and device ID. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
Model restriction: This API can be used only in the stage model.
System API: This is a system API.
System capability: SystemCapability.DistributedDataManager.DataShare.Provider
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the target device. |
predicates | dataSharePredicates.DataSharePredicates | Yes | DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic. |
Return value
Type | Description |
---|---|
Promise<KVStoreResultSet> | Promise that returns no value. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100001 | Over max limits. |
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let resultSet: distributedKVStore.KVStoreResultSet = xxx;
let predicates = new dataSharePredicates.DataSharePredicates();
predicates.prefixKey("batch_test_string_key");
kvStore.getResultSet('localDeviceId', predicates).then((result) => {
console.info('Succeeded in getting result set');
resultSet = result;
}).catch((err: BusinessError) => {
console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
});
kvStore.closeResultSet(resultSet).then(() => {
console.info('Succeeded in closing result set');
}).catch((err: BusinessError) => {
console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSize
getResultSize(query: Query, callback: AsyncCallback<number>): void
Obtains the number of results that match the specified Query object for this device. This API uses an asynchronous callback to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
callback | AsyncCallback<number> | Yes | Callback invoked to return the number of results obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
console.info('Succeeded in putting batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSize(query, async (err, resultSize) => {
if (err != undefined) {
console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting result set size');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSize
getResultSize(query: Query): Promise<number>
Obtains the number of results that match the specified Query object for this device. This API uses a promise to return the result.
System capability: SystemCapability.DistributedDataManager.KVStore.Core
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<number> | Promise used to return the number of results obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSize(query).then((resultSize) => {
console.info('Succeeded in getting result set size');
}).catch((err: BusinessError) => {
console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}
getResultSize
getResultSize(deviceId: string, query: Query, callback: AsyncCallback<number>): void;
Obtains the number of results that matches the specified device ID and Query object. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the device to which the KVStoreResultSet object belongs. |
query | Query | Yes | Query object to match. |
callback | AsyncCallback<number> | Yes | Callback invoked to return the number of results obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries, async (err) => {
if (err != undefined) {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in putting batch');
const query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSize('localDeviceId', query, async (err, resultSize) => {
if (err != undefined) {
console.error(`Failed to get resultSize.code is ${err.code},message is ${err.message}`);
return;
}
console.info('Succeeded in getting resultSize');
});
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSize.code is ${error.code},message is ${error.message}`);
}
getResultSize
getResultSize(deviceId: string, query: Query): Promise<number>
Obtains the number of results that matches the specified device ID and Query object. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().
System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
Parameters
Name | Type | Mandatory | Description |
---|---|---|---|
deviceId | string | Yes | ID of the device to which the KVStoreResultSet object belongs. |
query | Query | Yes | Query object to match. |
Return value
Type | Description |
---|---|
Promise<number> | Promise used to return the number of results obtained. |
Error codes
For details about the error codes, see Distributed KV Store Error Codes.
ID | Error Message |
---|---|
15100003 | Database corrupted. |
15100005 | Database or result set already closed. |
Example
import { BusinessError } from '@ohos.base';
let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
let entries: distributedKVStore.Entry[] = [];
for (let i = 0; i < 10; i++) {
let key = 'batch_test_string_key';
let entry: distributedKVStore.Entry = {
key: key + i,
value: {
type: distributedKVStore.ValueType.STRING,
value: 'batch_test_string_value'
}
}
entries.push(entry);
}
kvStore.putBatch(entries).then(async () => {
console.info('Succeeded in putting batch');
}).catch((err: BusinessError) => {
console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
});
let query = new distributedKVStore.Query();
query.prefixKey("batch_test");
kvStore.getResultSize('localDeviceId', query).then((resultSize) => {
console.info('Succeeded in getting resultSize');
}).catch((err: BusinessError) => {
console.error(`Failed to get resultSize.code is ${err.code},message is ${err.message}`);
});
} catch (e) {
let error = e as BusinessError;
console.error(`Failed to get resultSize.code is ${error.code},message is ${error.message}`);
}
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