Re: Show lossy heap block info in EXPLAIN ANALYZE for bitmap heap scan

> I wrote:
> > Robert Haas wrote:
> > > I'd be wary of showing a desired value unless it's highly likely to
> > > be accurate.

> > The desired value is accurately estimated based on (a) the total
> > number of exact/lossy pages stored in the TIDBitmap and (b) the
> > following equation in tbm_create(), except for the GIN case where
> > lossy pages are added to the TIDBitmap by tbm_add_page().

I've found there is another risk of overestimating the desired memory space
for a BitmapAnded TIDBitmap.  I'm inclined to get rid of the estimation
functionality from the patch completely, and leave it for future work.
Attached is a new version of the patch, which shows only fetch block
information and memory usage information.  I'll add this to the upcoming CF.

Thanks,

Best regards,
Etsuro Fujita