"Marc G. Fournier" <scrappy@postgresql.org> writes:
> I believe that this is what Oleg et al tap into with the tsearch2 stuff,
> no? I have someone asking me about it, and want to make sure that I'm
> telling him the right answer ... is this what GiST is?
Better ask what he means by "external" exactly. I think I've heard some
people use the phrase "external index" to mean any index that's not
actually part of the table itself; which makes all our index types
"external". (As a counterexample, imagine a table that is itself
organized as a btree.)
regards, tom lane