Re: An Idea for planner hints

On Aug 15, 2006, at 13:55 , Peter Eisentraut wrote:

> Jim C. Nasby wrote:
>>> Meet EXPLAIN ANALYZE.
>>
>> Which does no good for apps that you don't control the code on. Even
>> if you do control the code, you have to find a way to stick EXPLAIN
>> ANALYZE in front of every query, and figure out how to deal with
>> what's comming back.
>
> It would not be hard to create an "auto explain analyze" mode that
> implicitly runs EXPLAIN ANALYZE along with every query and logs the
> result. On its face, it sounds like an obviously great idea. I just
> don't see how you would put that to actual use, unless you want to
> read
> server logs all day long. Grepping for query duration and using the
> statistics views are much more manageable tuning methods. In my view
> anyway.

Also [and this has been brought up before], explain analyze doesn't
make any effort to highlight the actual discrepancies from the plan.
If it could drop an arrow or an asterisk where, for example, the
numbers are off by an order of magnitude, it would make a big
difference.