Re: [HACKERS] using a btree index in order by clause?

>
> Hi,
>
> I'm wondering if we can use btree index to sort the results in a
> certain condition. The idea is, if the order-items in the order by
> clause have a btree index, then why we need to sort them again?
>
> I'm starting to look at the executor code. However this kind of
> "optimization" might be better to be done in the optimizer, I don't
> know.

FYI, often, using an index to sort a tables is SLOWER than loading all the
rows into psort and sorting them, because the index causes random seeks
all over the table.

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