This is a weird question
We lately moved to exadata (do not know if relevant.
I am running a simple select query with a in clause. lets say:
----------
select a, b
from myTable
where request_id in (-100, 100)
--------
it takes between 0.3 (the best of the best) to 90 seconds to return an answer
This table contain around 9 BILLION rows
the index are working great because when I do
select a, b
from myTable
where request_id = 100
union
select a, b
from myTable
where request_id = -100
it takes lest then 0.01 second constantly
Any idea?