2011/10/14 Tom Lane :
> Measure the number of all-visible pages for use in index-only scan costing.
>
> Add a column pg_class.relallvisible to remember the number of pages that
> were all-visible according to the visibility map as of the last VACUUM
> (or ANALYZE, or some other operations that upda
Measure the number of all-visible pages for use in index-only scan costing.
Add a column pg_class.relallvisible to remember the number of pages that
were all-visible according to the visibility map as of the last VACUUM
(or ANALYZE, or some other operations that update pg_class.relpages).
Use rela
