OH_Predicates

typedef struct {...} OH_Predicates

Overview

Defines a predicates object.

Since: 10

Related module: RDB

Header file: oh_predicates.h

Member Variables

Name	Description
int64_t id	Unique identifier of the OH_Predicates struct.

Member Functions

Name	Description
OH_Predicates (equalTo)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are equal to the specified value.
OH_Predicates (notEqualTo)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are not equal to the specified value. This method is equivalent to "!=" in SQL statements.
OH_Predicates (beginWrap)(OH_Predicates *predicates)	Pointer to the function used to add a left parenthesis to the predicates. This method is equivalent to "(" in SQL statements.
OH_Predicates (endWrap)(OH_Predicates *predicates)	Pointer to the function used to add a right parenthesis to the predicates. This method is equivalent to ")" in SQL statements.
OH_Predicates (orOperate)(OH_Predicates *predicates)	Pointer to the function used to add the OR operator to the predicates. This method is equivalent to OR in SQL statements.
OH_Predicates (andOperate)(OH_Predicates *predicates)	Pointer to the function used to add the AND operator to the predicates. This method is equivalent to AND in SQL statements.
OH_Predicates (isNull)(OH_Predicates predicates, const char field)	Pointer to the function used to create a predicates object to search for the field values that are null. This method is equivalent to IS NULL in SQL statements.
OH_Predicates (isNotNull)(OH_Predicates predicates, const char field)	Pointer to the function used to create a predicates object to search for the field values that are not null. This method is equivalent to IS NOT NULL in SQL statements.
OH_Predicates (like)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are similar to the specified string. This method is equivalent to LIKE in SQL statements.
OH_Predicates (between)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are within the specified range. This method is equivalent to BETWEEN in SQL statements.
OH_Predicates (notBetween)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are out of the specified range. This method is equivalent to NOT BETWEEN in SQL statements.
OH_Predicates (greaterThan)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are greater than the specified value. This method is equivalent to ">" in SQL statements.
OH_Predicates (lessThan)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the records that are less than the given value in the specified field. This method is equivalent to "<" in SQL statements.
OH_Predicates (greaterThanOrEqualTo)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are greater than or equal to the specified value. This method is equivalent to ">=" in SQL statements.
OH_Predicates (lessThanOrEqualTo)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the records that are less than or equal to the specified valueObject in the specified field. This method is equivalent to "<=" in SQL statements.
OH_Predicates (orderBy)(OH_Predicates predicates, const char field, OH_OrderType type)	Pointer to the function used to create a predicates object to sort the values in the specified column in ascending or descending order. This method is equivalent to ORDER BY in SQL statements.
OH_Predicates (distinct)(OH_Predicates *predicates)	Pointer to the function used to create a predicates object to filter out duplicate records. This method is equivalent to DISTINCT in SQL statements.
OH_Predicates (limit)(OH_Predicates *predicates, unsigned int value)	Pointer to the function used to create a predicates object to specify the maximum number of records. This method is equivalent to LIMIT in SQL statements.
OH_Predicates (offset)(OH_Predicates *predicates, unsigned int rowOffset)	Pointer to the function used to create a predicates object to specify the start position of the query result. This method is equivalent to OFFSET in SQL statements.
OH_Predicates (groupBy)(OH_Predicates predicates, char const const *fields, int length)	Pointer to the function used to create a predicates object to group the results by the specified columns. This method is equivalent to GROUP BY in SQL statements.
OH_Predicates (in)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are within the specified range. This method is equivalent to IN in SQL statements.
OH_Predicates (notIn)(OH_Predicates predicates, const char field, OH_VObject *valueObject)	Pointer to the function used to create a predicates object to search for the field values that are out of the specified range. This method is equivalent to NOT IN in SQL statements.
OH_Predicates (clear)(OH_Predicates *predicates)	Pointer to the function used to clear a predicates instance.
int (destroy)(OH_Predicates predicates)	Destroys an OH_Predicates object and reclaims the memory occupied.

Member Function Description

equalTo()

OH_Predicates *(*equalTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are equal to the specified value.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Pointer to the column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

notEqualTo()

OH_Predicates *(*notEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are not equal to the specified value.
This method is equivalent to "!=" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

beginWrap()

OH_Predicates *(*beginWrap)(OH_Predicates *predicates)

Description

Pointer to the function used to add a left parenthesis to the predicates.
This method is equivalent to "(" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
OH_Predicates *	Predicates with a left parenthesis.

endWrap()

OH_Predicates *(*endWrap)(OH_Predicates *predicates)

Description

Pointer to the function used to add a right parenthesis to the predicates.
This method is equivalent to ")" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
OH_Predicates *	Predicates with a right parenthesis.

orOperate()

OH_Predicates *(*orOperate)(OH_Predicates *predicates)

Description

Pointer to the function used to add the OR operator to the predicates.
This method is equivalent to OR in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
OH_Predicates *	Predicates with the OR condition.

andOperate()

OH_Predicates *(*andOperate)(OH_Predicates *predicates)

Description

Pointer to the function used to add the AND operator to the predicates.
This method is equivalent to AND in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
OH_Predicates *	Predicates with the AND condition.

isNull()

OH_Predicates *(*isNull)(OH_Predicates *predicates, const char *field)

Description

Pointer to the function used to create a predicates object to search for the field values that are null.
This method is equivalent to IS NULL in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

isNotNull()

OH_Predicates *(*isNotNull)(OH_Predicates *predicates, const char *field)

Description

Pointer to the function used to create a predicates object to search for the field values that are not null.
This method is equivalent to IS NOT NULL in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

like()

OH_Predicates *(*like)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are similar to the specified string.
This method is equivalent to LIKE in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

between()

OH_Predicates *(*between)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are within the specified range.
This method is equivalent to BETWEEN in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

notBetween()

OH_Predicates *(*notBetween)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are out of the specified range.
This method is equivalent to NOT BETWEEN in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

greaterThan()

OH_Predicates *(*greaterThan)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are greater than the specified value.
This method is equivalent to ">" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

lessThan()

OH_Predicates *(*lessThan)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the records that are less than the given value in the specified field.
This method is equivalent to "<" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

greaterThanOrEqualTo()

OH_Predicates *(*greaterThanOrEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are greater than or equal to the specified value.
This method is equivalent to ">=" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

lessThanOrEqualTo()

OH_Predicates *(*lessThanOrEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the records that are less than or equal to the specified valueObject in the specified field.
This method is equivalent to "<=" in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

orderBy()

OH_Predicates *(*orderBy)(OH_Predicates *predicates, const char *field, OH_OrderType type)

Description

Pointer to the function used to create a predicates object to sort the values in the specified column in ascending or descending order.
This method is equivalent to ORDER BY in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Column name in the database table.
OH_VObject type	Sorting type, which is an OH_VObject.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

distinct()

OH_Predicates *(*distinct)(OH_Predicates *predicates)

Description

Pointer to the function used to create a predicates object to filter out duplicate records.
This method is equivalent to DISTINCT in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
OH_Predicates *	Predicates that can filter out duplicate records.

limit()

OH_Predicates *(*limit)(OH_Predicates *predicates, unsigned int value)

Description

Pointer to the function used to create a predicates object to specify the maximum number of records.
This method is equivalent to LIMIT in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
unsigned int value	Maximum number of data records.

Returns

Type	Description
OH_Predicates *	Predicates that specify the maximum number of records.

offset()

OH_Predicates *(*offset)(OH_Predicates *predicates, unsigned int rowOffset)

Description

Pointer to the function used to create a predicates object to specify the start position of the query result.
This method is equivalent to OFFSET in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
unsigned int rowOffset	Start position, which is a positive integer.

Returns

Type	Description
OH_Predicates *	Predicates that specify the start position of the returned result.

groupBy()

OH_Predicates *(*groupBy)(OH_Predicates *predicates, char const *const *fields, int length)

Description

Pointer to the function used to create a predicates object to group the results by the specified columns.
This method is equivalent to GROUP BY in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
char const const fields	Names of columns to group.
int length	Length of fields.

Returns

Type	Description
OH_Predicates *	Predicates that group rows with the same value.

in()

OH_Predicates *(*in)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are within the specified range.
This method is equivalent to IN in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Pointer to the column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

notIn()

OH_Predicates *(*notIn)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)

Description

Pointer to the function used to create a predicates object to search for the field values that are out of the specified range.
This method is equivalent to NOT IN in SQL statements.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.
const char *field	Pointer to the column name in the database table.
OH_VObject *valueObject	Pointer to an OH_VObject instance, indicating the value to be matched with the predicate.

Returns

Type	Description
OH_Predicates *	Predicates that match the specified field.

clear()

OH_Predicates *(*clear)(OH_Predicates *predicates)

Description

Pointer to the function used to clear a predicates instance.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
OH_Predicates *	Cleared predicates.

destroy()

int (*destroy)(OH_Predicates *predicates)

Description

Pointer to the function used to destroy an OH_Predicates object and reclaim the memory occupied.

Since: 10

Parameters

Name	Description
OH_Predicates *predicates	Pointer to the OH_Predicates instance.

Returns

Type	Description
int	Returns RDB_OK if the operation is successful; returns an error code otherwise.

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OH_Predicates

Overview

Member Variables

Member Functions

Member Function Description

equalTo()

notEqualTo()

beginWrap()

endWrap()

orOperate()

andOperate()

isNull()

isNotNull()

like()

between()

notBetween()

greaterThan()

lessThan()

greaterThanOrEqualTo()

lessThanOrEqualTo()

orderBy()

distinct()

limit()

offset()

groupBy()

in()

notIn()

clear()

destroy()

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