Re: generic options for explain

Peter Eisentraut wrote:
> On Monday 25 May 2009 18:02:53 Tom Lane wrote:
>> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>>> This is all much more complicated than what I proposed, and I fail to
>>> see what it buys us. I'd say that you're just reinforcing the point I
>>> made upthread, which is that insisting that XML is the only way to get
>>> more detailed information will just create a cottage industry of
>>> beating that XML output format into submission.
>> The impression I have is that (to misquote Churchill) XML is the worst
>> option available, except for all the others. We need something that can
>> represent a fairly complex data structure, easily supports addition or
>> removal of particular fields in the structure (including fields not
>> foreseen in the original design), is not hard for programs to parse,
>> and is widely supported --- ie, "not hard" includes "you don't have to
>> write your own parser, in most languages". How many realistic
>> alternatives are there?
>
> I think we are going in the wrong direction. No one has said that they want a
> machine-readable EXPLAIN format.

That is not true. Tool developers like pgAdmin (I know that one for
sure), phpPgAdmin (I think they have said it too) and third party tools
have asked for this.

Right now we parse the EXPLAIN output. Which doesn't get easier with
each new thing we add to it :-)

It would be very nice to have it tool parseable.

I'm also fairly certain that people using auto_explain would have use
for a format that's easier to parse.

> What people really want is optional additional information in the human-
> readable format. Giving them a machine readable format does not solve the
> problem. Giving them a machine readable format with all-or-none of the
> optional information and saying "figure it out yourself" does not solve
> anything either. The same people who currently complain will continue to
> complain.

I agree that this is a separate issue. But that doesn't mean they don't
both exist.

//Magnus