Peter Geoghegan <peter@2ndquadrant.com> writes:
> On 17 June 2012 17:01, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> The killer reason why it must be like that is that you can't use hash
>> methods on text if text equality is some unknown condition subtly
>> different from bitwise equality.
> Fair enough, but I doubt that we need to revert the changes made in
> this commit to texteq in addition to the changes I'd like to see in
> order to be semantically self-consistent. That is because there is
> often a distinction made between equality and equivalence, and we
> could adopt this distinction.
How exactly do you plan to shoehorn that into SQL? You could invent
some nonstandard "equivalence" operator I suppose, but what will be the
value? We aren't going to set things up in such a way that we can't
use hash join or hash aggregation in queries that use the regular "="
operator. IMO there just aren't going to be enough people who care to
use a non-default operator.
regards, tom lane