Re: Bug: When user-defined AM is used, the index path cannot be selected correctly

Quan Zongliang <quanzongliang(at)yeah(dot)net> writes:
> New patch attached.
> It seems that partitions do not use AM other than btree and hash.
> Rewrite only indxpath.c and check if it is a custom AM.

This seems drastically underdocumented, and the test you're using
for extension opclasses is wrong. What we need to know before
applying match_boolean_index_clause is that a clause using
BooleanEqualOperator will be valid for the index. That's got next
door to nothing to do with whether the opclass is default for
the index AM. A non-default opclass might support that operator,
and conversely a default one might not (although I concede it's
not that easy to imagine what other set of operators-on-boolean
an extension opclass might be interested in).

I think we need something more like the attached.

regards, tom lane