Re: More WITH

On Mon, Aug 17, 2015 at 1:41 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Peter Geoghegan <pg@heroku.com> writes:
>> On Mon, Aug 17, 2015 at 10:22 AM, Josh Berkus <josh@agliodbs.com> wrote:
>>> Would be tricky.  We don't currently have any way to wrap an EXPLAIN in
>>> any larger statement, do we?  Would be very useful for automated query
>>> analysis, though.
>
>> No. In the grammar, ExplainStmt expects the EXPLAIN to be at the
>> top-level. Having it work any other way would require significant
>> refactoring.
>
> You can use EXPLAIN as the source of rows in a plpgsql FOR-over-query
> loop, so there's a workaround available that way when you need to read
> EXPLAIN output programmatically.  I'm not convinced there's sufficient
> value in trying to make EXPLAIN a full-fledged subquery otherwise.

I think a lot of people would find that handy - I would - but I don't
know how hard it is.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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