On 25/04/2010 9:07 AM, Andre Lopes wrote:
> Hi,
>
> I need to use the BEGIN WORK; and COMMIT WORK; to lock a table when I'am
> doing a SELECT and UPDATE operation.
PostgreSQL's server-side functions do *not* support transaction
management. They're functions that're used inside an existing transaction.
However, if you do not explcitly BEGIN a transaction before calling your
function, the statement your function runs in will start and stop its
own transaction. In other words, these two things are equivalent:
BEGIN;
SELECT my_function();
COMMIT;
and
SELECT my_function();
(outside an existing transaction)
Because your function is *always* inside a transaction, it can always
acquire locks and the like. It doesn't need to explicitly start a
transaction first.
--
Craig Ringer
