Re: auto_explain sample rate

On 2 June 2015 at 15:11, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> wrote:

>
>
> 2015-06-02 9:07 GMT+02:00 Craig Ringer <craig(at)2ndquadrant(dot)com>:
>
>>
>> For the majority of users I'm sure it's sufficient to just have a sample
>> rate.
>>
>> Anything that's trying to match individual queries could be interested in
>> all sorts of different things. Queries that touch a particular table being
>> one of the more obvious things, or queries that mention a particular
>> literal. Rather than try to design something complicated in advance that
>> anticipates all needs, I'm thinking it makes sense to just throw a hook in
>> there. If some patterns start to emerge in terms of useful real world
>> filtering criteria then that'd better inform any more user accessible
>> design down the track.
>>
>
> same method can be interesting for interactive EXPLAIN ANALYZE too. TIMING
> has about 20%-30% overhead and usually we don't need a perfectly exact
> numbers
>

I don't understand what you are suggesting here.

--
Craig Ringer http://www.2ndQuadrant.com/
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