Re: count() for a select statement?

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От snpe
Тема Re: count() for a select statement?
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Msg-id 200210012032.45912.snpe@snpe.co.yu
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Ответ на count() for a select statement?  (Jean-Christian Imbeault <jc@mega-bucks.co.jp>)
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On Tuesday 01 October 2002 07:46 pm, Jean-Christian Imbeault wrote:
> Is there an efficient way to get a count of the number of rows returned
> by this kind of query?
>
> select id from products where name ILIKE 'TNT' UNION select id from
> products where name ILIKE 'ATOM' UNION select id from products where
> name ILIKE 'BOB'
>
> I don't need any of the data returned, just a row count. The way I do it
> now is to execute the query and use (in PHP) pg_numrows() on the result
> set. But that mean the whole result set is being sent back to me when
> all I need is a count ...
>
> I've tried select count( select id from ...) but that didn't work ;)
>

You try :
select count(*)
from (select id from ...)

regards
haris peco

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