Thank you Jeff.
There are 7 million rows satisfying fk_id_client = 20045. There is an index on fk_id_client, now I added a composite (fk_id_client, id) index but that did not help.
I see the point of what you are saying, but still don't understand how these two situations (
asc vs.
desc) are not symmetrical. I mean, there
is an ascending index on
JOB_MEMORY.id, so why does it matter which end I am picking the data from?
The thing is, even when I force Postgres to use the ascending index on
id, it's still orders of magnitude slower than the
desc version (even when that one goes through the index backwards).
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Re: Huge difference between ASC and DESC ordering Sent from the
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