Alvaro Herrera <alvhe...@2ndquadrant.com> writes: > Tom Lane wrote: >> Sooner or later we are going to need to go to 8-byte TOAST object >> identifiers. Maybe we should think about doing that sooner not later >> rather than trying to invent some anti-wraparound solution here.
> Umm, it seems to me like we need this fixed in supported branches, not > just 9.7, so I don't think 8-byte toast IDs are a reasonable solution at > this point. I think the problem is pretty hypothetical until you get to consuming a substantial part of the OID space within any one toast table, at which point you're going to need 8-byte toast OIDs. Improving that situation seems like something we can define as a future feature. (Note that I do not believe for a moment that Andres has actually exhibited such a problem in his test case. He'd have needed several TB worth of TOAST space to get to that point.) >> In principle, you could support existing TOAST tables and pointers >> containing 4-byte IDs in parallel with the new ones. Not sure how >> pg_upgrade would handle it exactly though. > I suppose the real problem is that there's no way to have a mix of 4- > and 8-byte identifiers in the same toast table. I suppose we could have > two toast tables for each regular table, but that sounds pretty painful. Hmm. It's not impossible by any means, since you could tell by looking at a toast OID which table it was in. And that way might provide a less painful upgrade process for an existing table that grew to the point of needing bigger OIDs. regards, tom lane -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers