Re: Planning counters in pg_stat_statements (using pgss_store)

On 2020/03/30 17:03, Julien Rouhaud wrote:
> On Mon, Mar 30, 2020 at 01:56:43PM +0900, Fujii Masao wrote:
>>
>>
>> On 2020/03/29 15:15, Julien Rouhaud wrote:
>>> On Fri, Mar 27, 2020 at 03:42:50PM +0100, Julien Rouhaud wrote:
>>>> On Fri, Mar 27, 2020 at 2:01 PM Fujii Masao <masao.fujii@oss.nttdata.com> wrote:
>>>>>
>>>>
>>>>> So what I'd like to say is that the information that users are interested
>>>>> in would vary on each situation and case. At least for me it seems
>>>>> enough for pgss to report only the basic information. Then users
>>>>> can calculate to get the numbers (like total_time) they're interested in,
>>>>> from those basic information.
>>>>>
>>>>> But of course, I'd like to hear more opinions about this...
>>>>
>>>> +1
>>>>
>>>> Unless someone chime in by tomorrow, I'll just drop the sum as it
>>>> seems less controversial and not a blocker in userland if users are
>>>> interested.
>>>
>>> Done in attached v11, with also the s/querytext/query_text/ discrepancy noted
>>> previously.
>>
>> Thanks for updating the patch! But I still think query_string is better
>> name because it's used in other several places, for the sake of consistency.
> 
> You're absolutely right.  That's what I actually wanted to do given your
> previous comment, but somehow managed to miss it, sorry about that and thanks
> for fixing.
> 
>> So I changed the argument name that way and commit the 0001 patch.
>> If you think query_text is better, let's keep discussing this topic!
>>
>> Anyway many thanks for your great job!
> 
> Thanks a lot!
> 
>>
>>>>>> I also exported BufferUsageAccumDiff as mentioned previously, as it seems
>>>>>> clearner and will avoid future useless code churn, and run pgindent.
>>>>>
>>>>> Many thanks!! I'm thinking to commit this part separately.
>>>>> So I made that patch based on your patch. Attached.
>>>>
>>>> Thanks! It looks good to me.
>>>
>>> I also kept that part in a distinct commit for convenience.
>>
>> I also pushed 0002 patch. Thanks!
>>
>> I will review 0003 patch again.
> 
> And thanks for that too :)

While testing the patched pgss, I found that the patched version
may track the statements that the original version doesn't.
Please imagine the case where the following queries are executed,
with pgss.track = top.

     PREPARE hoge AS SELECT * FROM t;
     EXPLAIN EXECUTE hoge;

The pgss view returned "PREPARE hoge AS SELECT * FROM t"
in the patched version, but not in the orignal version.

Is this problematic?

Regards,

-- 
Fujii Masao
NTT DATA CORPORATION
Advanced Platform Technology Group
Research and Development Headquarters