EXTFNAPIV4_DESCRIBE_PARM_TABLE_HAS_REWIND Attribute (Get)

The EXTFNAPIV4_DESCRIBE_PARM_TABLE_HAS_REWIND attribute indicates if the parameter supports rewind. Used in a describe_parameter_get scenario.

Data Type

a_sql_byte

Description

Indicates whether a producer can support rewind. Valid only for table arguments.

You must also provide an implementation of the rewind table callback (_rewind_extfn() ) if you plan on setting DESCRIBE_PARM_TABLE_HAS_REWIND to true. The server will fail to execute the UDF if the callback method is not provided.

Usage

The UDF asks if a table input argument supports rewind. As a prerequisite, the UDF must request rewind using DESCRIBE_PARM_TABLE_REQUEST_REWIND before you can use this property.

Returns

On success, returns sizeof(a_sql_byte).

On failure, returns one of the generic describe_parameter errors, or:

EXTFNAPIV4_DESCRIBE_BUFFER_SIZE_MISMATCH – get error returned if the describe_buffer is not the size of a_sql_byte.
EXTFNAPIV4_DESCRIBE_INVALID_STATE – get error error returned if the state is not greater than Annotation.
EXTFNAPIV4_DESCRIBE_NON_TABLE_PARAMETER – get error returned if the UDF attempts to get this attribute on a parameter that is not a table.
EXTFNAPIV4_DESCRIBE_INVALID_PARAMETER – get error returned if the UDF attempts to get this attribute on the result table.

Query Processing States

Valid in:

Optimization state
Plan Building state
Execution state