| From: | Stephan Szabo <sszabo(at)megazone23(dot)bigpanda(dot)com> |
|---|---|
| To: | Rajesh Kumar Mallah <mallah(at)trade-india(dot)com> |
| Cc: | <pgsql-sql(at)postgresql(dot)org> |
| Subject: | Re: planner question.. |
| Date: | 2003-04-17 14:12:37 |
| Message-ID: | 20030417071102.V87131-100000@megazone23.bigpanda.com |
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| Thread: | |
| Lists: | pgsql-sql |
On Thu, 17 Apr 2003, Rajesh Kumar Mallah wrote:
> I think there shud be more documentation on
> understanding EXPLAIN (ANALYZE) output.
> once i found an webpage but lost it.
I believe there's one inside the docs on performance or optimization.
>
> where do u see its expecting 5000 not 100000?
> > > | Aggregate (cost=23982.58..23982.58 rows=1 width=0) (actual
> > > | time=22872.97..22872.97 rows=1 loops=1) | ->
> > > | Seq Scan on profile_master (cost=0.00..23970.40 rows=4871 width=0)
> > > | (actual time=328.44..22730.69 rows=102090 loops=1) |
In the Seq Scan line, it's got rows=4871. That's the number it thinks are
going to match the filter/index condition.
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