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[kbn]

Hi,

I have a table T1 with an index I1 with columns C1, C2, C3 in sequence.

Which of the below query is effective?

select * from T1
where C1 = 'a'
and C2 = 'b'
and C3 >= 'c'

OR

select * from T1
where C2 = 'a'
and C1 = 'b'
and C3 >= 'c'

thanks,
kbn

[vkphani]

[acevedo]

btw, both queries are not equal.

[videlord]

first of all, different result would be returned by the 2 queries. the execute time may different depend on how may result returned
second, the access path would be the same (most case), index scan, with 3 match columns