Re: [GENERAL] Transactions within a function body - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: [GENERAL] Transactions within a function body
Date
Msg-id 20081002154022.GD4151@alvh.no-ip.org
Whole thread Raw
In response to Re: [GENERAL] Transactions within a function body  ("Gurjeet Singh" <singh.gurjeet@gmail.com>)
Responses Re: [GENERAL] Transactions within a function body  ("Bob Henkel" <bob.henkel@gmail.com>)
List pgsql-hackers
Gurjeet Singh escribió:

> I have seen this feature being asked for, and this work-around suggested so
> many times. If plpgql does it internally, why not provide a clean interface
> for this? Is there some road-block, or that nobody has ever tried it?

Initially we aimed at just exposing SAVEPOINT and ROLLBACK TO in
functions, but ran into the problem that the SPI stack needs to be dealt
with appropriately and you can't do it if the user is able to modify it
arbitrarily by calling transaction-modifying commands.  That's when the
EXCEPTION idea came up.  We never went back and studied whether we could
have fixed the SPI limitation, but it's not trivial.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

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