Re: New EXPLAIN option: ALL

On 2019-May-13, David Fetter wrote:

> I tried changing it to EXEC (EXPLAIN EXECUTE is already a thing), but
> got a giant flock of reduce-reduce conflicts along with a few
> shift-reduce conflicts.

After eyeballing the giant patch set you sent[1], I think EXEC is a
horrible keyword to use -- IMO it should either be the complete word
EXECUTE, or we should pick some other word. I realize that we do not
want to have different sets of keywords when using the legacy syntax (no
parens) vs. new-style (with parens), but maybe we should just not
support the EXECUTE keyword in the legacy syntax; there's already a
number of options we don't support in the legacy syntax (BUFFERS,
TIMING), so this isn't much of a stretch.

IOW if we want to change ANALYZE to EXECUTE, I propose we change it in
the new-style syntax only and not the legacy one. So:

EXPLAIN ANALYZE SELECT ... -- legacy syntax
EXPLAIN (EXECUTE) SELECT ... -- new-style
EXPLAIN (ANALYZE) SELECT ... -- we still support ANALYZE as an alias, for compatibility

this should not cause a conflict with EXPLAIN EXECUTE, so these all
should work:

EXPLAIN ANALYZE EXECUTE ...
EXPLAIN (EXECUTE) EXECUTE ...
EXPLAIN (ANALYZE) EXECUTE ...

[1] I think if you just leave out the GUC print from the changes, it
becomes a reasonable patch series.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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