Re: dropped columns, tupDesc

"Sergey E. Koposov" <math@sai.msu.ru> writes:
> I've recently  proposed a patch 
> http://archives.postgresql.org/pgsql-patches/2006-02/msg00165.php
> to fix an old problem with dropped columns, but recently 
> http://archives.postgresql.org/pgsql-patches/2006-02/msg00246.php
> Neil Conway have discovered the problem even with the patch. After looking 
> on the problem it seems that my patch just discovered an additional set of 
> incosistencies of Postgres in the work with droppped columns. 

> I looked in the source of those problems and it seems that I have found 
> it, but it is situated rather deep in Postgres and I don't have enough 
> expertise too judge it. So I would be interested if someone clarify the 
> issue for me and how the problem should be fixed.

This is not really fixable without some infrastructure to flush cached
plans when the things they depend on change.  That's a system-wide
problem and it'd be a mistake to spend much time hacking localized
stopgaps.

Neil has been making noises about working on the real problem, but I dunno
how far along he is.
        regards, tom lane