On 4/11/18 17:08, Peter Geoghegan wrote:
>> However, I don't see any point in defining collations here, because
>> INCLUDE attributes exist solely for index-only scans. So, index just
>> can return value of INCLUDE attribute "as is", no point to do something
>> with collation.
>>
>> So, I propose to disable collations for INCLUDE attributes.
> Hmm. I'm not sure that that's exactly the right thing to do. We seem
> to want to have case-insensitive collations in the future. The fact
> that you can spell out collation name in ON CONFLICT's unique index
> inference specification suggests this, for example. I think that a
> collation is theoretically allowed to affect the behavior of equality,
> even though so far we've never tried to make that work for any
> collatable datatype.
But in this case it doesn't even do equality comparison, it just returns
the value.
--
Peter Eisentraut http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services