Re: count * performance issue

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От Andrew Sullivan
Тема Re: count * performance issue
Дата
Msg-id 20080311143439.GA1465@crankycanuck.ca
обсуждение исходный текст
Ответ на Re: count * performance issue  (Matthew <matthew@flymine.org>)
Список pgsql-performance
On Tue, Mar 11, 2008 at 02:19:09PM +0000, Matthew wrote:
> of rows with IS NULL, then someone changes a row, then you find the count
> of rows with IS NOT NULL. Add the two together, and there may be rows that
> were counted twice, or not at all.

Only if you count in READ COMMITTED.

A


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