Re: VACUUM ANALYZE is faster than ANALYZE?

On Wed, Feb 22, 2012 at 8:13 AM, Nicolas Barbier
<nicolas(dot)barbier(at)gmail(dot)com> wrote:
> 2012/2/22 Robert Haas <robertmhaas(at)gmail(dot)com>:
>
>> On Tue, Feb 21, 2012 at 9:00 AM, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> wrote:
>>
>>> I had to reply to query about usage VACUUM ANALYZE or ANALYZE. I
>>> expected so ANALYZE should be faster then VACUUM ANALYZE.
>>>
>>> But is not true. Why?
>>
>> I'm pretty sure that VACUUM ANALYZE *will* be faster than ANALYZE in
>> general, because VACUUM has to scan the whole table, and ANALYZE only
>> a fixed-size subset of its pages.
>
> It sounds like you just said the opposite of what you wanted to say.

Yeah, I did. Woops. Let me try that again:

ANALYZE should be faster; reads only some pages.

VACUUM ANALYZE should be slower; reads them all.

Dunno why Pavel's seeing the opposite without more info.

--
Robert Haas
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