Re: [HACKERS] SELECT DISTINCT i FROM dtest ORDER BY j

> The trouble is that if you have several tuples with the same i and
> different j, doing the DISTINCT first implies throwing away all but
> one of those tuples.  Which one do you keep?  It matters because
> some of those tuples might sort differently than others.
> 
> As far as I can see, this combination of features is not well-defined on
> its surface.  You have to make some additional assumptions (about which
> of the possible j values is kept for sorting) in order to define a
> unique result.

That is an interesting argument.  It suggests it should not be a TODO
item.  I can see cases where you would want to do the DISTINCT before
the ORDER BY, so the current behavior seems correct.

Removing it from TODO list.

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