On Fri, Jul 12, 2013 at 1:23 PM, Vincenzo Romano <vincenzo.rom...@notorand.it> wrote: > Hi all > I'm making some experiments with table archiving and I'd like to > "replace" a full table F with an empty one E. > In order to do this I see only one way: > > ALTER TABLE F RENAME TO T; > ALTER TABLE E RENAME TO F; > ALTER TABLE T RENAME TO E; -- optional > > This implies there's a moment when the full table doesn't exist. > Would a transaction enclosure ensure that the table F will be always > available to all clients?
If I get it right using transaction boundaries around the DDL will prevent clients to query the F table until the transaction ends, and this is due to the locking of the alter table. In other words, a query performed against the F table while the transaction is running will simply locks without generating any error. Hope this helps. Luca -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
