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SQLSetStmtOption Mapping

  • Άρθρο

When an application calls SQLSetStmtOption through an ODBC 3.x driver, the call to

SQLSetStmtOption(StatementHandle, fOption, vParam)

will result as follows:

  • If fOption indicates an ODBC-defined statement attribute that is a string, the Driver Manager calls

    SQLSetStmtAttr(StatementHandle, fOption, ValuePtr, SQL_NTS)

  • If fOption indicates an ODBC-defined statement attribute that returns a 32-bit integer value, the Driver Manager calls

    SQLSetStmtAttr(StatementHandle, fOption, ValuePtr, 0)

  • If fOption indicates a driver-defined statement attribute, the Driver Manager calls

    SQLSetStmtAttr(StatementHandle, fOption, ValuePtr, BufferLength)

In the preceding three cases, the StatementHandle argument is set to the value in hstmt, the Attribute argument is set to the value in fOption, and the ValuePtr argument is set to the value as vParam.

Because the Driver Manager does not know whether the driver-defined statement attribute needs a string or 32-bit integer value, it has to pass in a valid value for the StringLength argument of SQLSetStmtAttr. If the driver has defined special semantics for driver-defined statement attributes and needs to be called using SQLSetStmtOption, it must support SQLSetStmtOption.

If an application calls SQLSetStmtOption to set a driver-specific statement option in an ODBC 3.x driver and the option was defined in an ODBC 2.x version of the driver, a new manifest constant should be defined for the option in the ODBC 3.x driver. If the old manifest constant is used in the call to SQLSetStmtOption, the Driver Manager will call SQLSetStmtAttr with the StringLength argument set to 0.

When an application calls SQLSetStmtAttr to set SQL_ATTR_USE_BOOKMARKS to SQL_UB_ON in an ODBC 3.x driver, the SQL_ATTR_USE_BOOKMARKS statement attribute is set to SQL_UB_FIXED. SQL_UB_ON is the same constant as SQL_UB_FIXED. The Driver Manager passes SQL_UB_FIXED through to the driver. SQL_UB_FIXED has been deprecated in ODBC 3.x, but an ODBC 3.x driver must implement it to work with ODBC 2.x applications that use fixed-length bookmarks.

For an ODBC 3.x driver, the Driver Manager no longer checks to see if Option is in between SQL_STMT_OPT_MIN and SQL_STMT_OPT_MAX, or is greater than SQL_CONNECT_OPT_DRVR_START.