Robert Treat wrote: > On Wednesday 18 February 2009 10:47:25 Tom Lane wrote: > > Gregory Stark <st...@enterprisedb.com> writes: > > > Tom Lane <t...@sss.pgh.pa.us> writes: > > >> No, but this would just be the same situation that prevails after > > >> OID-counter wraparound, so I don't see a compelling need for us to > > >> change the OID counter in the new DB. If the user has done the Proper > > >> Things (ie, made unique indexes on his OIDs) then it won't matter. > > >> If he didn't, his old DB was a time bomb anyway. > > > > > > Also I wonder about the performance of skipping over thousands or even > > > millions of OIDs for something like a toast table. > > > > I think that argument is a red herring. In the first place, it's > > unlikely that there'd be a huge run of consecutive OIDs *in the same > > table*. In the second place, if he does have such runs, the claim that > > he can't possibly have dealt with OID wraparound before seems pretty > > untenable --- he's obviously been eating lots of OIDs. > > > > Yeah, but its not just lots... it's lots and lots of lots. Sure, I have > multi-billion row _tables_ now, but I know I ran systems for years "back in > the day" when we used oids in user tables, and they never made it to oid > wraparound terratory, because they just didn't churn through that much data. > > > But having said that, there isn't any real harm in fixing the OID > > counter to match what it was. You need to run pg_resetxlog to set the > > WAL position and XID counter anyway, and it can set the OID counter too. > > > > +1 for doing this, otherwise we need some strong warnings in the migrator > docs > about this case imho.
One compromise is outputting the pg_resetxlog command to the terminal, and suggesting they run it only if they need to. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers