FWIW: COUNT(*) is probably better than COUNT(id). COUNT(*) checks how many rows there are, and there are sometimes efficiencies in that such as checking the high water mark. COUNT(id) checks how many ids are not null, which means every value must be checked (unless it is a not null column and the optimizer is smart enough to rewrite the query.)

In reply to Re: Use of uninitialized value in lc by chacham
in thread Use of uninitialized value in lc by Alice Wonder

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