Re: Add min and max execute statement time in pg_stat_statement

On 21/01/15 17:32, Andrew Dunstan wrote:
>
> On 01/21/2015 11:21 AM, Arne Scheffer wrote:
>>
>>
>>
>> Why is it a bad thing to call the column "stddev_samp" analog to the
>> aggregate function or make a note in the documentation, that the
>> sample stddev is used to compute the solution?
>
>...
>
> But I will add a note to the documentation, that seems reasonable.
>

I agree this is worth mentioning in the doc.

In any case here some review from me:

We definitely want this feature, I wished to have this info many times.

The patch has couple of issues though:

The 1.2 to 1.3 upgrade file is named pg_stat_statements--1.2-1.3.sql and
should be renamed to pg_stat_statements--1.2--1.3.sql (two dashes).

There is new sqrtd function for fast sqrt calculation, which I think is
a good idea as it will reduce the overhead of the additional calculation
and this is not something where little loss of precision would matter
too much. The problem is that the new function is actually not used
anywhere in the code, I only see use of plain sqrt.

--
Petr Jelinek http://www.2ndQuadrant.com/
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