Re: Expose options to explain? (track_io_timing)

On Tue, Oct 14, 2014 at 1:04 PM, Joshua D. Drake <jd(at)commandprompt(dot)com> wrote:
> On 10/14/2014 10:01 AM, Robert Haas wrote:
>> Hmm. IIRC, there are only two use cases for I/O timing at present:
>> pg_stat_statements (which really only makes sense if it's turned on or
>> off system-wide) and EXPLAIN. Rather than inventing more GUC
>> machinery, I think we could just add an explain flag called "IO". So
>> you could do:
>>
>> EXPLAIN (ANALYZE, IO) SELECT ....
>>
>> And that would gather I/O stats even if it's turned off system-wide.
>> Or you could do:
>>
>> EXPLAIN (ANALYZE, IO false) SELECT ....
>>
>> That can't really be allowed to suppress gathering the I/O stats for
>> this query if the sysadmin wants those stats for all queries. But it
>> could suppress the print-out.
>
> I think the first one makes the most sense.

It would be both or neither, not one or the other. All EXPLAIN
options take true/false arguments; but "true" can be omitted for
brevity.

--
Robert Haas
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