| From: | "Craig A(dot) James" <cjames(at)modgraph-usa(dot)com> |
|---|---|
| To: | Stephan Szabo <sszabo(at)megazone(dot)bigpanda(dot)com> |
| Cc: | pgsql-performance(at)postgresql(dot)org |
| Subject: | Re: Identical Queries |
| Date: | 2007-03-01 22:41:39 |
| Message-ID: | 45E756A3.5020604@modgraph-usa.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-performance |
Stephan Szabo wrote:
> I tried posting to the bugs, and they said this is a better question for here.
> I have to queries. One runs in about 2 seconds. The other takes upwards
> of 2 minutes. I have a temp table that is created with 2 columns. This
> table is joined with the larger database of call detail records.
> However, these 2 queries are handled very differently.
Even for a temporary table, you should run ANALYZE on it after you fill it but before you query or join to it. I found out (the hard way) that a temporary table of just 100 rows will generate dramatically different plans before and after ANALYZE.
Craig
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