Re: count * performance issue

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On Tue, 11 Mar 2008, Tino Wildenhain wrote:
And certain, qualified definitions of "accurate" as well. Race condition?

You mean in a three-state-logic? null, not null and something different?

True, False, and FILE_NOT_FOUND.

No, actually I was referring to a race condition. So, you find the count 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.

Matthew

--
It's one of those irregular verbs - "I have an independent mind," "You are
an eccentric," "He is round the twist."
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