Martijn van Oosterhout <kleptog@svana.org> writes:
> AFAICS two big problems with using an index type:
> 1. The index isn't told when the tuple is deleted.
Hm, good point ... we could make it do so but for ordinary deletes it'd
be a waste of cycles to open indexes at all.
> 2. The server expects to be able to lookup an index.
Only if there is a WHERE operator that matches the index's opclass.
This hypothetical index type would probably have one dummy opclass
containing no operators.
regards, tom lane