Re: [GENERAL] Weird ..... (a=1 or a=2) <> (a=2 or a=1)

On 5/19/06, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> This only affects the 7.4 and 8.0 branches, because earlier and later
> versions of Postgres don't use this technique for detecting duplicates.
> But it's surprising we didn't find it before.

hm. about a year ago I reported a case where the database allowed
multiple records with the same p-key which were causing problems with
dump/reload from 8.0->8.1. It was pretty rare, but it looked like
under certain circumstances unique constraint was not getting applied.
I was unable to reproduce it, though.

Is it possible that this bug was the cause of that particular problem?

Merlin