Re: generic explain options v3 - RR Review

Hi Robert, Hi All,

Patch applies with some offset changes, code changes look sensible, I 
personally like the new syntax and the features it may allow in future. One, 
possibly big, gripe remains though:
The formerly valid statement which cannot be written without the parentheses 
and stay semantically equivalent:
EXPLAIN (SELECT 1 ORDER BY 1) UNION ALL (SELECT 2 ORDER BY 1);
is now not valid anymore (The added %prec UMINUS causes the first '(' to be 
recognize as start of the option list as intended).
This currently can only be resolved by using an option list like:
EXPLAIN (VERBOSE OFF) ...
Its also currently impossible to use an empty set of parentheses to resolve 
this - this could easily be changed though.

I have to admit I don't see a nice solution here except living with the 
incompatibility... Perhaps somebody has a better idea?

Andres

PS: The 'offset corrected' version I tested with is attached