Overriding default precision and scale for numeric data types

Function calls to	Setting	Override
SQLBindCol or SQLSetDescField	SQL_DESC_TYPE field in an ARD is set to SQL_C_NUMERIC	SQL_DESC_SCALE field in the ARD is set to 0 and the SQL_DESC_PRECISION field is set to a driver-defined default precision. See (1).
SQLBindParameter or SQLSetDescField	SQL_DESC_SCALE field in an APD is set to SQL_C_NUMERIC	SQL_DESC_SCALE field in the ARD is set to 0 and the SQL_DESC_PRECISION field is set to a driver-defined default precision. This is true for input, input/output, or output parameters. See (1).
SQLGetData	Data is returned into an SQL_C_NUMERIC structure	Default SQL_DESC_SCALE and SQL_DESC_PRECISION fields are used. See (2).

1 If the defaults are not acceptable for an application, the application can call the SQLSetDescField or SQLSetDescRec to set the SQL_DESC_SCALE or SQL_DESC_PRECISION field.

2 If the defaults are not acceptable, the application must call SQLSetDescRec or SQLSetDescField to set the fields and then call SQLGetData with a TargetType of SQL_ARD_TYPE to use the values in the descriptor fields.