Re: Does RAISE EXCEPTION rollback previous commands in a stored function?
От | Alexander Farber |
---|---|
Тема | Re: Does RAISE EXCEPTION rollback previous commands in a stored function? |
Дата | |
Msg-id | CAADeyWhtXG0uznEhyE68CPjGS5gQhnDmJ8f05ULCxkPmDfwnGg@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: Does RAISE EXCEPTION rollback previous commands in a stored function? (Albe Laurenz <laurenz.albe@wien.gv.at>) |
Ответы |
Re: Does RAISE EXCEPTION rollback previous commands in a
stored function?
|
Список | pgsql-general |
Thank you, this is very helpful, just 1 little question:
Why do you write just EXCEPTION?On Wed, Mar 2, 2016 at 11:18 AM, Albe Laurenz <laurenz.albe@wien.gv.at> wrote:
Alexander Farber wrote:
> how to set such a savepoint inside of a stored function?
>
> Can I call "START TRANSACTION", and then at some point later in the same stored function call RAISE
> EXCEPTION?
I realize that what I wrote must be confusing.
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.
В списке pgsql-general по дате отправления: