On Mon, Nov 13, 2017 at 12:40 PM, Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
>> Do I have to explicitly specify collation when using ORDER by on that column for index and abbreviated keys to be used?
>
> Only if you didn't define the column with a per-column collation initially.
BTW, if you specifically want to quickly verify whether or not
abbreviated keys were used, you can do that by setting "trace_sort =
on", and possibly setting "client_min_messages = LOG", too.
There should be quite a bit of debug output from that that
specifically mentions abbreviated keys.
--
Peter Geoghegan