Re: Rationalizing EXPLAIN VERBOSE output

Gavin Sherry wrote:
> On Sun, 10 Mar 2002, Bruce Momjian wrote:
>
> > Tom Lane wrote:
>
> > > Seems kinda ugly. But maybe same idea with repeated VERBOSE,
> > > a la some Unix commands ("more -v's get you more detail"):
> > >
> > > EXPLAIN [ANALYZE] [VERBOSE] [ VERBOSE ... ] statement;
> > >
>
> >
> > I was never a fan of the -v -v more-verbose options, and I don't see any
> > case where we use such behavior in our code. We do use detail levels
> > for debug, and that is fairly common.
>
> I agree. This is fine under Unix, but command arguments are not really a
> grammar. Yacc doesn't enjoy terminal repetition and for good reason: it
> usually suggests a clumsy grammar.
>
> Personally, I think that Tom's code should go into standard EXPLAIN.

I am confused. Which grammar do you like?

> As for how to returning explain data as a SELECT. I think I prefer
> Oracle's idea of output tables with a Postgres twist. EXPLAIN could then
> be something like:
>
> EXPLAIN [VERBOSE] [SET ID='...' ] [INTO [TEMP] <table>] <query>
>
> If 'table' exists, EXPLAIN would check if it is a valid explain output
> table (correct attr names, types) and if so insert the results of explain,
> one tuple per line of output. ID would be a text identifier of the output.
>
> If the table didn't exist, it would be created. TEMP means that the table
> is removed at the end of the session.
>
> Is this overkill?

That was my initial reaction. :-)

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