SQL Language Changes

Reserved Words
Execution Results

It will be necessary to pay attention to some changes in the SQL language implementation.

Reserved Words

While some new reserved keywords are introduced, generally the overall list of reserved words has been reduced dramatically by making Firebird's parser grammar allow most of the previously reserved non-standard keywords as non-reserved. The list of those still reserved, and of SQL standard keywords newly reserved, is available in the chapter Reserved Words and Changes.

Execution Results

Some changes will now cause exceptions during run-time execution of queries, including those that are run during the execution of the gbak utility code (backups and restores).

Malformed String Errors

Well-formedness checks are now performed on UNICODE_FSS strings and text blobs. If new or existing UNICODE_FSS is malformed, it will now cause exceptions at execution time.

Logic Change in SET Clause

Previously, when the SET clause of the UPDATE statement assigned new values to columns, the new value replaced the old value immediately. If the same column was assigned or assigned to more than once, the current value would be that of the assignment most recently done. In other words, previously, assignment order mattered.

To bring Firebird in line with the standard, from this version forward, only the original value of a column is accessible to any assignment in the SET clause.

For a period, it is possible to revert to the legacy behavior by setting the temporary parameter OldSetClauseSemantics in firebird.conf. This parameter will be deprecated and removed in future releases.