Re: Index-only scans

Heikki Linnakangas wrote:
> Even if we don't solve the visibility
> map problem, just allowing the executor to evaluate quals that are not
> directly indexable using data from the index, would be useful. For
> example, "SELECT * FROM foo WHERE textcol LIKE '%bar%', and you have a
> b-tree index on textcol, the planner could choose a full-index-scan,
> apply the '%bar%' filter on the index tuples, and only fetch those heap
> tuples that match that qual.

Interesting, I had not considered that. You are using the index as a
single-column table that can be scanned more quickly than the heap.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +