Andres Freund <andres@anarazel.de> writes:
> On 2019-01-21 18:14:31 -0500, Tom Lane wrote:
>> I don't think that's relevant. The issues there were about whether
>> a pg_index row update ought to cause an invalidation of the relcache
>> entry for the index's table (not the one for the index, which it
>> already takes care of). That seems very questionable to me --- the
>> potentially-invalidatable info ought to be in the index's relcache entry,
>> not its parent table's entry, IMO.
> Well, we've plenty of information about indexes in the table's
> relcache. Among other things, the list of indexes, bitmaps of indexed
> attributes, which index is the primary key, etc is all maintained
> there... So I don't really see a material difference between the
> constraint and the index case.
The difference is that we don't support index redefinitions that could
change any of those properties.
regards, tom lane