Re: bitmap scans, btree scans, and tid order

"Jeffrey W. Baker" <jwbaker@acm.org> writes:
> I see that Tom has already done the infrastructure work by adding
> getmulti, but getmulti isn't used by nodeIndexscan.c, only
> nodeBitmapIndexscan.c.  Will btree index scans be executed by creating
> in-memory bitmaps in 8.1, or will some scans still be executed the usual
> way?

We aren't going to remove the existing indexscan behavior, because
bitmap scans lose the ordering of the underlying index.  There are many
situations where that ordering is important.  (See for instance the
recent changes to make MAX/MIN use that behavior.)
        regards, tom lane