Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> writes:
> 2011/12/23 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
>> Tomas Vondra <tv(at)fuzzy(dot)cz> writes:
>>> The motivation for this patch was that collection timing data often
>>> causes performance issues and in some cases it's not needed. But is this
>>> true for row counts?
>> Perhaps more to the point, is there a use case for collecting timing
>> data without row counts? I find it hard to visualize a valid reason.
> yes - a searching of bad prediction
No, because timing alone proves nothing at all. The machine could just
have been overloaded.
regards, tom lane