The SQL Server driver fully supports all core and extended ODBC SQL grammar with the following exceptions.
| Non-supported grammar | Description |
|---|---|
| DAYOFWEEK | The scalar function DAYOFWEEK is not supported when connected to SQL Server 4.2x. The function is supported when connected to SQL Server 6.x. |
| DELETE | The WHERE CURRENT OF cursor_name clause (positioned delete statement) is not supported when connected to SQL Server 4.2x. The clause is supported when connected to SQL Server 6.x. |
| DROP INDEX | table_name and index_name must be used instead of just index_name. |
| IEF | None of the clauses in the Integrity Enhancement Facility (IEF) are supported when connected to SQL Server 4.2x. All of the clauses are supported when connected to SQL Server 6.x except the CASCADE and RESTRICT clauses. |
| MAX, MIN | The DISTINCT keyword is not supported for these set functions. |
| SELECT | The FOR UPDATE OF clause of the SELECT statement is not supported when connected to SQL Server 4.2x. The clause is supported when connected to SQL Server 6.x. |
| UPDATE | The WHERE CURRENT OF cursor_name clause (positioned UPDATE statement) is not supported when connected to SQL Server 4.2x. The clause is supported when connected to SQL Server 6.x. |
| USER | When connected to SQL Server version 6.0 and earlier, the USER keyword is not supported, except in the DEFAULT clause of the IEF. |