Re: Performance problem. Could it be related to 8.3-beta4?

Greg Smith <gsmith@gregsmith.com> writes:
> The only thing I noticed in your original explain plans that was different
> between the two was:
> 8.2:
>                 Merge Cond: ((ut.n_time = ui.n_time) AND
> ((ut.usuario)::text = "inner"."?column4?"))
> 8.3:
>                 Merge Cond: ((ut.n_time = ui.n_time) AND
> ((ut.usuario)::text = (ui.usuario_nome)::text))

I believe that is just a cosmetic change: the EXPLAIN code in 8.2 and
before tended to punt (and print "?columnN?") for any but the simplest
references to subplan node outputs, whereas 8.3 will (in theory) get it
right all the time.  With no other visible differences, there's no
reason to think these plans are different.

            regards, tom lane