I wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> This is cool, but on first blush your changes to
>> add_paths_to_joinrel() appear to be total nonsense. I think the
>> problem is that have_nonmergeable_clause is really a misnomer - it's
>> not clear until you read through the whole diff that this won't get
>> set for inner/left joins.
> Yeah, I wasn't totally satisfied with that variable name either.
> Do you have a better idea?
On reflection, how about inverting the flag's value and calling it
mergejoin_allowed or some such?
regards, tom lane