Re: generic options for explain

On May 26, 2009, at 8:15 AM, Peter Eisentraut <peter_e@gmx.net> wrote:

> On Monday 25 May 2009 18:02:53 Tom Lane wrote:
>> Robert Haas <robertmhaas@gmail.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.  OK, there are historically about  
> three
> people that want one, but they have already solved the problem of  
> parsing the
> current format.  And without having writtens such a parser myself I  
> think that
> the current format is not inherently hard 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.

Peter,

The check is in the mail. :-)

In all seriousness, I have no problem at all with providing machine- 
readable formats, but the problem you're describing here is definitely  
my primary pain point.

...Robert