Alexander Farber wrote: > On Wed, Mar 2, 2016 at 11:18 AM, Albe Laurenz <laurenz.albe@xxxxxxxxxx> wrote: >> You cannot use START TRANSACTION, BEGIN, SAVEPOINT, COMMIT or ROLLBACK >> inside a function. A function always runs within one transaction. >> >> Savepoints or subtransactions are written with a BEGIN ... EXCEPTION >> block in PL/pgSQL, so you could write: >> >> DECLARE FUNCTION .... AS >> $$BEGIN >> /* UPDATE 1 */ >> UPDATE ...; >> BEGIN /* sets a savepoint */ >> /* UPDATE 2, can cause an error */ >> UPDATE ...; >> EXCEPTION >> /* rollback to savepoint, ignore error */ >> WHEN OTHERS THEN NULL; >> END; >> END;$$; >> >> Even if UPDATE 2 throws an error, UPDATE 1 will be committed. > Thank you, this is very helpful, just 1 little question: > > > Why do you write just EXCEPTION? > > > Shouldn't it be RAISE EXCEPTION? That's something entirely different, see http://www.postgresql.org/docs/current/static/plpgsql-control-structures.html#PLPGSQL-ERROR-TRAPPING The above construct *catches* the exception, which might be raised by the UPDATE statement. Yours, Laurenz Albe -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
