Re: Aggregate functions with FROM clause and ROW_COUNT diagnostics

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От Tom Lane
Тема Re: Aggregate functions with FROM clause and ROW_COUNT diagnostics
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Msg-id 8937.1526921696@sss.pgh.pa.us
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Ответ на Re: Aggregate functions with FROM clause and ROW_COUNT diagnostics  (Alexey Dokuchaev <danfe@nsu.ru>)
Ответы Re: Aggregate functions with FROM clause and ROW_COUNT diagnostics  (Alexey Dokuchaev <danfe@nsu.ru>)
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Alexey Dokuchaev <danfe@nsu.ru> writes:
> Quick reality check
> question: are count(*) vs. count(_) equivalent above?

Only if _ is guaranteed non-null ... which, as a rowtype result, it
probably is.  But I'd use count(*) if you're concerned about speed.

            regards, tom lane

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