On Fri, Jul 6, 2012 at 5:22 PM, Craig Ringer <ringerc@xxxxxxxxxxxxx> wrote: > On 07/06/2012 09:45 PM, Stanislaw Pankevich wrote: > >> Question: Is there a possibility in PostgreSQL to do DELETE on many tables >> massively, like TRUNCATE allows. Like DELETE table1, table2, ...? > > > Yes, you can do it with a writable common table expression, but you wanted > version portability. > > WITH > discard1 AS (DELETE FROM test1), > discard2 AS (DELETE FROM test2 AS b) > SELECT 1; > > Not only will this not work in older versions (IIRC it only works with 9.1, > maybe 9.0 too but I don't see it in the documentation for SELECT for 9.0) > but I find it hard to imagine any performance benefit over simply sending > > DELETE FROM test1; DELETE FROM test2; > > This all smells like premature optimisation of cases that don't matter. What > problem are you solving with this? I will write tests for both massive TRUNCATE and DELETE (DELETE each_table) for my case with Ruby testing environment, and let you know about the results. For now, I think, I should go for massive TRUNCATE. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
