Data

Overview

Data (distributed data manager) supports persistence of various structured data on a single device, and data sync and sharing between a device and the cloud. It defines a series of data types for operations, such as data addition, deletion, modification, and query.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Since: 11

Summary

File

Name	Description
data_asset.h	Defines data asset structures. File to include: <database/data/data_asset.h> Library: libnative_rdb_ndk.z.so

Types

Name	Description
Data_AssetStatus	Defines an enum for data asset statuses.
Data_Asset	Defines a struct for a data asset.

Enums

Name	Description
Data_AssetStatus { ASSET_NULL = 0, ASSET_NORMAL, ASSET_INSERT, ASSET_UPDATE, ASSET_DELETE, ASSET_ABNORMAL, ASSET_DOWNLOADING }	Enumerates the data asset statuses.

Functions

Name	Description
OH_Data_Asset_SetName (Data_Asset *asset, const char *name)	Sets the name of a data asset.
OH_Data_Asset_SetUri (Data_Asset *asset, const char *uri)	Sets the absolute path (URI) of a data asset in the system.
OH_Data_Asset_SetPath (Data_Asset *asset, const char *path)	Sets the relative path of a data asset in the application sandbox directory.
OH_Data_Asset_SetCreateTime (Data_Asset *asset, int64_t createTime)	Sets the creation time for a data asset.
OH_Data_Asset_SetModifyTime (Data_Asset *asset, int64_t modifyTime)	Sets the last modification time for a data asset.
OH_Data_Asset_SetSize (Data_Asset *asset, size_t size)	Sets the size of a data asset.
OH_Data_Asset_SetStatus (Data_Asset *asset, Data_AssetStatus status)	Sets the status of a data asset.
OH_Data_Asset_GetName (Data_Asset *asset, char *name, size_t *length)	Obtains the name of a data asset.
OH_Data_Asset_GetUri (Data_Asset *asset, char *uri, size_t *length)	Obtains the absolute path of a data asset.
OH_Data_Asset_GetPath (Data_Asset *asset, char *path, size_t *length)	Obtains the relative path of a data asset.
OH_Data_Asset_GetCreateTime (Data_Asset *asset, int64_t *createTime)	Obtains the creation time of a data asset.
OH_Data_Asset_GetModifyTime (Data_Asset *asset, int64_t *modifyTime)	Obtains the last modification time of a data asset.
OH_Data_Asset_GetSize (Data_Asset *asset, size_t *size)	Obtains the space occupied by a data asset.
OH_Data_Asset_GetStatus (Data_Asset *asset, Data_AssetStatus *status)	Obtains the status of a data asset.
OH_Data_Asset_CreateOne ()	Creates a Data_Asset instance.
OH_Data_Asset_DestroyOne (Data_Asset *asset)	Destroys a Data_Asset instance.
OH_Data_Asset_CreateMultiple (uint32_t count)	Creates multiple Data_Asset instances.
OH_Data_Asset_DestroyMultiple (Data_Asset **assets, uint32_t count)	Destroys multiple Data_Asset instances.

Type Description

Data_Asset

typedef struct Data_Asset Data_Asset

Description

Defines a struct for a data asset.

It provides information about a data asset.

Since: 11

Enum Description

Data_AssetStatus

enum Data_AssetStatus

Description

Enumerates the data asset statuses.

Value	Description
ASSET_NULL	The data asset is null.
ASSET_NORMAL	The data asset is in normal status.
ASSET_INSERT	The data asset is to be inserted to the cloud.
ASSET_UPDATE	The data asset is to be updated to the cloud.
ASSET_DELETE	The data asset is to be deleted from the cloud.
ASSET_ABNORMAL	The data asset is in abnormal status.
ASSET_DOWNLOADING	The data asset is being downloaded to a local device.

Function Description

OH_Data_Asset_CreateMultiple()

Data_Asset** OH_Data_Asset_CreateMultiple (uint32_t count)

Description

Creates multiple Data_Asset instances.

Since: 11

Parameters

Name	Description
count	Number of data assets to create.

Returns

Returns the pointer to the Data_Asset instance created if the operation is successful; returns null otherwise.

See

Data_Asset.

OH_Data_Asset_CreateOne()

Data_Asset* OH_Data_Asset_CreateOne ()

Description

Creates a Data_Asset instance.

Since: 11

Returns

Returns the pointer to the Data_Asset instance created if the operation is successful; returns null otherwise.

See

Data_Asset.

OH_Data_Asset_DestroyMultiple()

int OH_Data_Asset_DestroyMultiple (Data_Asset ** assets, uint32_t count )

Description

Destroys multiple Data_Asset instances.

Since: 11

Parameters

Name	Description
assets	Pointer to the Data_Asset instances to destroy.
count	Number of the Data_Asset instances to destroy.

Returns

Returns RDB_OK if the operation is successful; returns an error code otherwise. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset, OH_Rdb_ErrCode.

OH_Data_Asset_DestroyOne()

int OH_Data_Asset_DestroyOne (Data_Asset * asset)

Description

Destroys a Data_Asset instance.

Since: 11

Parameters

Name	Description
asset	Pointer to the Data_Asset instance to destroy.

Returns

Returns RDB_OK if the operation is successful; returns an error code otherwise. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset, OH_Rdb_ErrCode.

OH_Data_Asset_GetCreateTime()

int OH_Data_Asset_GetCreateTime (Data_Asset * asset, int64_t * createTime )

Description

Obtains the creation time of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
createTime	Ponter to the creation time obtained, in int64_t format.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_GetModifyTime()

int OH_Data_Asset_GetModifyTime (Data_Asset * asset, int64_t * modifyTime )

Description

Obtains the last modification time of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
modifyTime	Pointer to the last modification time obtained, in int64_t format.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_GetName()

int OH_Data_Asset_GetName (Data_Asset * asset, char * name, size_t * length )

Description

Obtains the name of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
name	Pointer to the data asset name obtained, in the form of a string.
length	Pointer to the length of the name.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_GetPath()

int OH_Data_Asset_GetPath (Data_Asset * asset, char * path, size_t * length )

Description

Obtains the relative path of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
path	Pointer to the relative path of the data asset obtained, in the form of a string.
length	Pointer to the length of the relative path.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_GetSize()

int OH_Data_Asset_GetSize (Data_Asset * asset, size_t * size )

Description

Obtains the space occupied by a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
size	Pointer to the data asset size obtained, in the format of size_t.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_GetStatus()

int OH_Data_Asset_GetStatus (Data_Asset * asset, Data_AssetStatus * status )

Description

Obtains the status of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
status	Pointer to the Data_AssetStatus obtained.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_GetUri()

int OH_Data_Asset_GetUri (Data_Asset * asset, char * uri, size_t * length )

Description

Obtains the absolute path (URI) of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
uri	Pointer to the absolute path of the data asset obtained, in the form of a string.
length	Pointer to the length of the URI.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_SetCreateTime()

int OH_Data_Asset_SetCreateTime (Data_Asset * asset, int64_t createTime )

Description

Sets the creation time for a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
createTime	Creation time to set.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_SetModifyTime()

int OH_Data_Asset_SetModifyTime (Data_Asset * asset, int64_t modifyTime )

Description

Sets the last modification time for a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
modifyTime	Last modification time to set.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_SetName()

int OH_Data_Asset_SetName (Data_Asset * asset, const char * name )

Description

Sets the name of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
name	Pointer to the name to set.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_SetPath()

int OH_Data_Asset_SetPath (Data_Asset * asset, const char * path )

Description

Sets the relative path of a data asset in the application sandbox directory.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
path	Pointer to the relative path to set.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_SetSize()

int OH_Data_Asset_SetSize (Data_Asset * asset, size_t size )

Description

Sets the size of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
size	Size of the data asset to set.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

OH_Data_Asset_SetStatus()

int OH_Data_Asset_SetStatus (Data_Asset * asset, Data_AssetStatus status )

Description

Sets the status of a data asset.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
status	Status to set. For details, see Data_AssetStatus.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset, Data_AssetStatus

OH_Data_Asset_SetUri()

int OH_Data_Asset_SetUri (Data_Asset * asset, const char * uri )

Description

Sets the absolute path (URI) of a data asset in the system.

Since: 11

Parameters

Name	Description
asset	Pointer to the target Data_Asset instance.
name	Pointer to the URI to set.

Returns

Returns an error code. For details about the error codes, see OH_Rdb_ErrCode.

See

Data_Asset

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