On Sat, Apr 24, 2010 at 6:29 PM, Simon Riggs <si...@2ndquadrant.com> wrote: > On Fri, 2010-04-23 at 22:52 -0400, Robert Haas wrote: >> Thoughts? > > Only a requirement: that we design this in a way that will allow temp > tables to be used during Hot Standby. I make not other comment.
For so long as local temporary tables put their catalog entries in pg_class, we're not going to be able to use them during Hot Standby. See the email I just sent elsewhere on this thread for a long term roadmap to getting out of that pickle. At least under the implementation I'm proposing here, making global temporary tables usable would be an easier nut to crack, because the catalog entries are a non-issue. There is one major problem, though: assigning a scratch relfilenode to the temporary table requires generating an OID, which we currently have no way to allow on the standby. Upthread I also proposed an implementation for unlogged tables (that is, contents don't survive a server bounce) which wouldn't have that problem either, although I haven't fully thought it through and there may very well be other issues. So in short: I don't think anything we're talking about it would make HS use harder, and some of it might make it easier. But probably some additional engineering effort dedicated specifically to solving the problems unique to HS would still be needed. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
