Available inPSQL, triggers only

TypeData row

DescriptionOLD contains the existing version of a database record just before a deletion or update. Starting with Firebird 2.0 it is read-only.


In multi-action triggers — introduced in Firebird 1.5 — OLD is always available. But if the trigger is fired by an INSERT, there is obviously no pre-existing version of the record. In that situation, reading from OLD will always return NULL; writing to it will cause a runtime exception.