Bruce Momjian <bruce@momjian.us> writes:
> On Wed, Aug 8, 2018 at 01:55:53PM +0300, KES wrote:
>> If such exclusion constraint would be marked as UNIQUE we can use it for FK while implementing temporal/bi-temporal
tables.
> Yes, it would work, but doing that only for equality would be surprising
> to many people because exclusion constraints are more general than
> equality comparisons.
In general, we should be discouraging people from using EXCLUDE syntax
with simple equality operators, not encouraging them to do so. It's
less efficient and less portable than a regular btree-based uniqueness
constraint. So I think this proposal is a bad idea regardless of
whether it'd be technically feasible or not.
regards, tom lane