Gregory Stark <stark@enterprisedb.com> writes:
> But that doesn't explain the bitmap ops being important. Hm. Actually
> having a lot of columns and then joining a lot of tables could mean
> having fairly large bitmapsets.
Yeah, but then you have a lot of *other* expensive operations too,
such as the aforementioned statistics-pushing. It's still pretty
mystifying why bitmapsets would be eating a noticeable fraction
of the total.
regards, tom lane