INF: SET SHOWLPLAN and the MS SQL Server ODBC Driver

MORE INFORMATION

SET SHOWPLAN is a proprietary Transact-SQL command for Microsoft SQL Server that can be used to obtain information about the execution plans that SQL Server builds for SQL statements. When this option is turned on in an ODBC environment:

   SQLExecDirect(hstmt, "SET SHOWPLAN ON", SQL_NTS);
				

the showplan information will be returned through SQLError().

After SET SHOWPLAN has been turned on, SQLExecute() or SQLExecDirect() will both return SQL_SUCCESS_WITH_INFO on successful calls. The application can retrieve the showplan output by then looping through calls to SQLError() until SQLError() returns SQL_NO_DATA_FOUND. Each call to SQLError() will return one line of showplan data in the following format:

   szSqlState="01000", *pfNativeError=6223,
   szErrorMsg="[Microsoft][ODBC SQL Server Driver][SQL Server] Table Scan"
				

where the actual showplan output is the part of the szErrorMsg string that comes after the literal [SQL Server]. The calls to SQLError() must be made immediately after the SQLExecute() or SQLExecDirect() function call that generates the output.