Re: Seq Scan

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Tyler Durden wrote:
Hi,
I'm having some problems in performance in a simple select count(id)
from.... I have 700 000 records in one table, and when I do:

# explain select (id) from table_name;
-[ RECORD 1 ]---------------------------------------------------------------- QUERY PLAN | Seq Scan on table_name (cost=0.00..8601.30 rows=266730 width=4)

I had created an index for id(btree), but still shows "Seq Scan".
What I'm doing wrong?

Thanks,
Tyler

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TIP 4: Have you searched our list archives?

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select count(*) will *always* do a sequential scan, due to the MVCC architecture. See archives for much discussion about this.

-Dan


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