Re: [HACKERS] Reporting planning time with EXPLAIN - Mailing list pgsql-hackers

Stephen Frost <sfrost@snowman.net> writes:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> I think it's an awful choice of name; it has nothing to do with either
>> the functionality or the printed name of the field.

> As an example, we might some day wish to include a summary of buffer
> information at the bottom too when 'buffers' is used.  The proposed
> 'summary' option would cover that nicely, but 'timing' wouldn't.  That's
> actually why I was thinking summary might be a good option to have.

What, would this option then turn off the total-time displays by default?
I do not see that being a reasonable thing to do.  Basically, you're
taking what seems like a very general-purpose option name and nailing
it down to mean "print planning time".  You aren't going to be able
to change that later.

> No, but consider how the docs for the current 'timing' option would have
> to be rewritten.

Well, sure, they'd have to be rewritten, but I think this definition
would actually be more orthogonal.

> We would also have to say something like "the default when not using
> 'analyze' is off, but with 'analyze' the default is on" which seems
> pretty grotty to me.

But the default for TIMING already does depend on ANALYZE.

> Then again, from a *user's* perspective, it should just be included by
> default.

Actually, the reason it hasn't gotten included is probably that the
use-case for it is very small.  If you just do psql \timing on an
EXPLAIN, you get something close enough to the planning time.  I don't
mind adding this as an option, but claiming that it's so essential
that it should be there by default is silly.  People would have asked
for it years ago if it were all that important.

> Having the summary option exposed would also provide a way for Andres to
> do what he wanted to originally from the referred-to thread.  There may
> be other pieces to address if the plan might involve platform-specific
> details about sorts, etc, but from what he was suggesting that wouldn't
> be an issue for his initial case, and as Robert mentioned on that
> thread, we could do something about those other cases too.  I don't
> think having 'timing' or 'whatever controls showing planning and total
> execution times at the bottom' would make sense as an option to disable
> showing platform-specific sort or hashing info though.

Again, you're proposing that you can add an option today and totally
redefine what it means tomorrow.  I do not think that's a plan.
        regards, tom lane