Jeremy Harris <jgh(at)wizmail(dot)org> writes:
> On 03/28/2010 05:27 PM, Tom Lane wrote:
>> This is intentional: the size estimates for a never-yet-analyzed
>> table are *not* zero. This is because people frequently create and load
>> up a table and then immediately query it without an explicit ANALYZE.
> Does the creation of an index also populate statistics?
IIRC, it will set the relpages/reltuples counts (though not any
more-complex statistics); but only if the table is found to not be
completely empty. Again, this is a behavior designed with common
usage patterns in mind, to not set relpages/reltuples to zero on a
table that's likely to get populated shortly.
regards, tom lane
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