| From: | "Edmar Wiggers" <edmar(at)brasmap(dot)com> |
|---|---|
| To: | "Alvar Freude" <alvar(dot)freude(at)merz-akademie(dot)de>, <pgsql-sql(at)postgresql(dot)org> |
| Subject: | RE: Using Array-Values in subselect |
| Date: | 2000-11-14 21:36:25 |
| Message-ID: | NEBBIAKDCDHFGJMLHCKIGEDFCBAA.edmar@brasmap.com |
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| Lists: | pgsql-sql |
IMHO you should use another table instead of an array.
Forget about reasonable speed when using IN sub-queries, you'll get a
sequential scan of the sub-query for every row in the master select. I've
heard the EXISTS operator provides far better performance.
In 7.1, there's a very nice solution: use the sub-query in the FROM clause
and make joins to it. Should be MUCH faster.
> But this causes an error because the array field just returns a string
> instead of seperated values. Is there a way to make arrays return sort
> of "real arrays" or something usable in a subselect in reasonable speed?
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