Re: Order by optimisations?

Hannu Krosing <hannu@skype.net> writes:
> On K, 2005-07-13 at 16:08 +0800, Christopher Kings-Lynne wrote:
>> Does it know that the input to the sort routine is already sorted and 
>> hence is a no-op?

> Yes

No, but in most cases this will use an index and hence will assume that
the index is responsible for ordering.
        regards, tom lane