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Archives of the TeradataForum
Message Posted: Wed, 20 Apr 2011 @ 11:14:43 GMT
Subj: | | Drop ji and then recreate it to avoid overhead? |
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From: | | Anomy Anom |
<-- Anonymously Posted: Wednesday, April 20, 2011 06:57 -->
I have the following query which is taking 5.50 mins to execute
SELECT LIST_NAME,ORIGINAL_NAME, COUNT(*)
FROM EMPLOYEE E, LIST L
WHERE E.LIST_ID=L.LIST_ID
GROUP BY LIST_NAME,ORIGINAL_NAME
Can someone help me in tuning the above query. Planning to use aggregate join index for this as users expect this query to run in approx
20 secs. To avoid overhead(insert s and update s), planning to create JI after every day s load is processed and then drop it just before next
days load as utilities are not supported with JI s. Any inputs are much appreciated.
Explain plan:
6) We do an all-AMPs SUM step to aggregate from Spool 3 (Last Use) by way
of an all-rows scan , grouping by field1 (L.LIST_NAME, E.ORIGINAL_name).
Aggregate Intermediate Results are computed globally, then placed in
Spool 5. The aggregate spool file will not be cached in memory. The
size of Spool 5 is estimated with no confidence to be 846,399 rows
(9,496,596,780 bytes). The estimated time for this step is 5 minutes
and 30 seconds.
Thanks
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