On 5/11/11 3:04 PM, Shaun Thomas wrote:
> The original query, with our very large tables, ran for over *two hours*
> thanks to a nested loop iterating over the subquery. My replacement ran
> in roughly 30 seconds. If we were using a newer version of PG, we could
> have used a CTE. But do you get what I mean? Temp tables are a fairly
> common technique, but how would a coder know about CTEs? They're pretty
> new, even to *us*.
For that matter, it would be even better if PostgreSQL realized that a
materialize of the subquery was a better execution plan, and just did it
for you.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com