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Archives of the TeradataForum
Message Posted: Mon, 05 Mar 2007 @ 15:11:41 GMT
Subj: | | Performance of a self join |
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From: | | Goutham P |
Can anyone please let me know if there is any way to improve the performance of a self join of large table? The size of this table is around
150 million records.
My query is something of this sort.
Select A.*
,value 1/ sum(value 2) over (partition by dim1, dim2, dim3, dim3 )
from
(
select
dim1,
dim2,
dim3,
metric 1/ metric 2 as value 2
from A
group by 1,2,3
) B
where A.dim1 = B.dim1
and A.dim2 = B.dim2
and A.dim3 = B.dim3
I am using a self join on table A with an OLAP function partition by. The performance is poor and looks like olap functions are not as
fast they are supposed to be.
Thanks
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