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SQLSetDescRec

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

This topic discusses SQLSetDescRec functionality that is specific to SQL Server Native Client.

SQLSetDescRec and Table-Valued Parameters

SQLSetDescRec can be used to set descriptor fields for table-valued parameters and table-valued parameter columns. Table-valued parameter columns are only available when the descriptor header field SQL_SOPT_SS_PARAM_FOCUS is set to the ordinal of a record that has SQL_DESC_TYPE set to SQL_SS_TABLE. For more information about SQL_SOPT_SS_PARAM_FOCUS, see SQLSetStmtAttr.

The following table describes the mapping between parameters and descriptor fields.

Parameter Related attribute for non-table-valued parameter types, including table-valued parameter columns Related attribute for table-valued parameters
Type SQL_DESC_TYPE SQL_SS_TABLE
SubType Ignored For records of type SQL_DATETIME or SQL_INTERVAL, set this to SQL_DESC_DATETIME_INTERVAL_CODE.
Length SQL_DESC_OCTET_LENGTH The length of the table-valued parameter type name. This can be SQL_NTS if the type name is null terminated, or zero if the table-valued parameter type name is not required.
Precision SQL_DESC_PRECISION SQL_DESC_ARRAY_SIZE
Scale SQL_DESC_SCALE Unused. This parameter should be zero.
DataPtr SQL_DESC_DATA_PTR in APD SQL_CA_SS_TYPE_NAME

This parameter is optional for stored procedure calls, and NULL can be specified if it is not required. This parameter must be specified for SQL statements that are not procedure calls.

DataPtr also serves as a unique value that the application can use to identify this table-valued parameter when variable row binding is used.
StringLengthPtr SQL_DESC_OCTET_LENGTH_PTR SQL_DESC_OCTET_LENGTH_PTR

For a table-valued parameter, this is the number of rows to transfer or SQL_DATA_AT_EXEC. This is a pointer to a value that holds the number of rows to transfer with SQLExecDirect.
IndicatorPtr SQL_DESC_INDICATOR_PTR SQL_DESC_INDICATOR_PTR

For more information about table-valued parameters, see Table-Valued Parameters (ODBC).

SQLSetDescRec Support for Enhanced Date and Time Features

The values allowed for date/time types are as follows:

Attribute Type SubType Length Precision Scale
datetime SQL_DATETIME SQL_CODE_TIMESTAMP 4 3 3
smalldatetime SQL_SQL_DATETIME SQL_CODE_TIMESTAMP 8 0 0
date SQL_DATETIME SQL_CODE_DATE 6 0 0
time SQL_SS_TIME2 0 10 0..7 0..7
datetime2 SQL_DATETIME SQL_CODE_TIMESTAMP 16 0..7 0..7
datetimeoffset SQL_SS_TIMESTAMPOFFSET 0 20 0..7 0..7

For more information, see Date and Time Improvements (ODBC).

SQLSetDescRec Support for Large CLR UDTs

SQLSetDescRec supports large CLR user-defined types (UDTs). For more information, see Large CLR User-Defined Types (ODBC).

See Also

SQLSetDescRec
ODBC API Implementation Details