Using Data Type Identifiers

Applications use data type identifiers in two ways: to describe their buffers to the driver, and to retrieve metadata about the result set from the driver so that they can determine what type of C buffers to use to store the data. Applications call the following functions to perform these tasks:

  • SQLBindParameter, SQLBindCol, and SQLGetData - to describe the C data type of application buffers.

  • SQLBindParameter - to describe the SQL data type of dynamic parameters.

  • SQLColAttribute and SQLDescribeCol - to retrieve the SQL data types of result set columns.

  • SQLDescribeParameter - to retrieve the SQL data types of parameters.

  • SQLColumns, SQLProcedureColumns, and SQLSpecialColumns - to retrieve the SQL data types of various schema information

  • SQLGetTypeInfo - to retrieve a list of supported data types

Data type identifiers are stored in the SQL_DESC_CONCISE_TYPE field of a descriptor. The descriptor functions SQLSetDescField and SQLSetDescRec can be used with the appropriate types to perform the tasks listed in the previous list. For more information, see SQLSetDescField.