Hi!
I have a very simple query
SELECT a, b FROM t ORDER BY a, b
I also have an index on t(a)
I have run ANALYZE
Also the number of repetitions of values of a in t is very low.
My view is that the execution should require little temporary space and
little time, something like:
for each different a(already ordered and of fast access from index) {
get all rows (usually 3/4, max arround 300)
sort this (little) subset
}
What is happening is that a tmp file of the size of the t is being
generated.
Is there any thing that I am not seeing? I there any way to change this
behaviour?
Thanks,
Tiago
--
Tiago Antão - RIPE NCC
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