Re: amount of join's and sequential access to the tables involved

El mié, 11-01-2012 a las 10:40 -0500, Tom Lane escribió:
> Gerardo Herzig <gherzig@fmed.uba.ar> writes:
> > Hi all. Im working on a 'simple' query with 7, 8 left joins. After the
> > 9nth join or so, explain analyze became to show the plan with many
> > tables being read in sequential fashion. Of course, this slows down the
> > query response in a factor on 10.
>
> increase join_collapse_limit, perhaps?
>
>             regards, tom lane
>

Crap, yes. That was it.
Just curious about one thing:

That query is part of a function. If i raise set_join_collapse in a psql
bash session, and then excecute the function, there is no changes. But
if i excecute the query directly in the psql session, it flys.

So, what happens, when a plsql function is excecuted, it takes is own
enviroment variables, or something like that?

Thanks again, Tom!

Gerardo