Re: Review: B-Tree emulation for GIN

Jeff Davis <pgsql(at)j-davis(dot)com> writes:
> Also, if extractQuery is non-strict, shouldn't we call it and see if it
> returns some useful keys?

Perhaps. One risk factor for approaching it that way is that there are
probably a lot of opclasses out there that haven't bothered to mark
these functions strict, since it's never mattered before. (A handy
example is that the brand new btree_gin opclasses did not bother, as
submitted; though in a fit of paranoia I made them do so before
committing.) If the extractQuery function isn't actually guarding
against this, you'll get a crash.

That's not a showstopper reason not to change, of course, but it does
mean that I'd like to see an actual use case for a non-strict GIN index
operator before taking any risk. Note that IS NULL isn't an operator,
so even if we were to try to support it in GIN, that would be a
different code path (just as it is in btree).

regards, tom lane