Does COUNT(*) always return a result?

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Published on 2010-03-31T10:31:26Z Indexed on 2010/03/31 10:33 UTC
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mysql

If a do a query such as:

SELECT COUNT(*) as num FROM table WHERE x = 'y'

Will it always return a result, even when the query doesn't match any record? Or do i need to validate and make sure a row is returned as the result?

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Does COUNT(*) always return a result? - Developer IT

Does COUNT(*) always return a result?

mysql

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mysql: Bind on unix socket: Permission denied

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