Re: PostgreSQL Query Speed Issues

Thanks again to everyone that has been assisting us with our query speed
issue. We have possibly found a reason why our views are running slow,
does anyone know if that could be our problem?
Please read below.
> We've started to test more of our queries that involve the view and we
> believe we may have come across a possible reason for the poor
> performance in our views.
> The view is pulling data from many tables as said before, one of them
> has a varchar(255) column (ColA) that is copied over into the view.
> However, in the view column definition, it is a varchar(2147483647).
> In the query we tested, we are running an equivalence check against this
> column, along with another varchar column of size 1 (ColB). When we
> remove the check against ColA the query returns in 2.5 seconds. When
> included it talks 200 seconds. There is almost no difference when the
> ColB check is removed (2.5s vs 2.3s).
>
> It is of our belief that this varchar(2147483647) could be causing
> performance problems. ColA might be defaulting to 2147483647 because it
> is being union-ed with the same column a couple of times in different
> circumstances. So we are wondering if there a way to set the column's
> varchar size in a view definition?

Thanks!