Re: Bitmap scans vs. the statistics views

Tom,

> The reason for this appears to be that the standard stats views
> disregard tuples_fetched for tables, but tuples_fetched is the only
> counter that's getting bumped in a bitmap scan.
>
> I could probably add some code to bump tuples_returned as well,
> but I wonder whether something more drastic isn't needed.  The
> stats views seem to be designed around the assumption that there
> are seqscans and indexscans and nothing else.  Do we need to
> expand the number of functions and rows to allow for a third basic
> scan type, or do we want to fuzz things up?
>
> Comments anyone?

Well, technically a bitmapscan is a different operation. So it should
probably have its own columns. Unless you're talking about an overhaul of
the stats views more drastic than that? If so, what?

I'm not clear on why bitmapscan doesn't bump tuples_returned. Can you
explain?

--
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco