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count(distinct id) slower then nested query?

Author

Topic

BorisCallens
Yak Posting Veteran

50 Posts

Posted - 2008-08-01 : 09:50:47

select count(distinct v.colorId) as totalCount
from searchView v
=> 5+ seconds

select count(t.kawnt) as totalCount
from (select distinct v.colorId as kawnt
from searchView v) as t
=> 1second

select distinct v.colorId
from searchView v
=> 1- seconds

Howcom does the extra complexity from the second query result in a faster query?

visakh16
Very Important crosS Applying yaK Herder

52326 Posts

Posted - 2008-08-01 : 13:14:06

have a had a look at query plans for first and second query?

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