On 2016-04-15 13:26:35 +1200, David Rowley wrote: > On 15 April 2016 at 13:02, Tom Lane <t...@sss.pgh.pa.us> wrote: > > David Rowley <david.row...@2ndquadrant.com> writes: > >> I proposed a fix over there, but it didn't go anywhere, probably > >> because Tom and Andres discussed just disallowing unique indexes on > >> system columns altogether. So, the attached patch does just that, and > >> also fixes up the replica identity bugs too, as it's still possible > >> that someone could create a unique index on a system column with an > >> old version, upgrade, then try to set the replica identity to that > >> index. We'd need to handle that correctly, so I fixed that too. > > > > AFAIR, what we were discussing was disallowing any index on a system > > column (other than OID). I do not see why only unique indexes are > > problematic for them; the semantic issues are independent of that. > > I have to admit that my thoughts only considered ctid, which I > imagined would have been OK to have an index on. As for the other > system columns (apart from OID), I agree.
What'd be the point of indexing ctid, and why would it be correct? Wouldn't, hm, HOT break it? Andres -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers