On Thu, Oct 31, 2013 at 10:59 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> However, if the index is unique, wouldn't
> scanning the index produce data that actually satisfies the longer sort
> key? It doesn't matter what the values of c,d are if there are no
> duplicates in the a,b columns. So maybe as a separate patch, we could
> look at claiming that a unique index satisfies the entire query_pathkeys
> if it matches the first N columns of that.
That would be really spiffy.
--
Robert Haas
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