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ora001 wrote:With no execution plans posted in your response, no. No idea why. Could be a zillion things.
CATS runs 10 times faster than the SELECT stmt, why?
Can you post couple from zillion(s) please?
I believe that you run the select statement and the blocks are placed on the buffer cache after that when you use CTAS the query runs faster because the blocks you need are already there.
clear the buffer cache before each run and post the results please
alter system flush buffer_cache;
Any thoughts?For one "create table .. as select" doesn't push the output to screen but the "select" does, so if the result is a lot off records the network to your PC becomes the bottleneck.
Can you provide some more info like the output of:
select count(*) FROM V WHERE A IN (1,2,3,4) GROUP BY A,B,C;Also do:
set autotrace onAnd run both commands and post only the autotrace info (Execution Plan + Statistics).
Are CATS as fast as CTAS? or am I deslyxic?