Re: How to avoid "Seq Scans"?

am Wed, dem 29.08.2007, um 11:15:21 +0200 mailte Vincenzo Romano folgendes:
> This loop is increadibly slow. Infact the friendly explain tells me
> that:
>
> test=# explain select * from t order by f2,f3;
> QUERY PLAN
> ---------------------------------------------------------------------------------
> Sort (cost=958786.20..970734.55 rows=4779338 width=28)
> Sort Key: f2,f3
> -> Seq Scan on t (cost=0.00..85501.38 rows=4779338 width=28)
>
> I'd like to know a hint about a technicque to avoid the sequential
> scan!

A 'select foo from bar' without a WHERE-condition forces a seq-scan
because _YOU_ want the whole table.

Andreas
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Andreas Kretschmer
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