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Is there any way to improve the efficiency of the following query? Currently, this query takes more than 15 min to complete (73 min of records) - and I have to check the whole database which is 7 days!!! (basically, this will take forever).

I tried the query without the indexes and it's MUCH slower. It takes just less than a minute (55 secs) to check 5 min between inputserialnumbers. There must be a better way.

Here is what I need. A query to return all inputserialnumber from either med or mrd where medstatus <> 'T' and ALL mrdstatus = NULL. med.inputserialnumbers are unique - mrd.inputserialnumbers are "1->many". To clarify, if at least 1 mrdstatus for mrd.inputserialnumber <> NULL, then I do not want that inputserialnumber.

SELECT /*+ INDEX(MED_MT_TB IX0101) */
med.inputserialnumber, inputconnectionnumber, rejectedmessage, destinationnumber, mrdstatus, medstatus
FROM med_mt_tb med, mrd_mt_tb mrd
WHERE
mrd.inputserialnumber = med.inputserialnumber(+) AND med.inputserialnumber > HEXTORAW('3FA6CDF541000013') AND -- Mon Nov 3 21:51:49 2003
med.inputserialnumber < HEXTORAW('3FA6DEF541000013') AND -- Mon Nov 3 23:04:21 2003
medstatus <> 'T' AND
med.inputserialnumber NOT IN (
SELECT /*+ INDEX(MRD_MT_TB IX0101) */
med.inputserialnumber FROM mrd_mt_tb
WHERE mrdstatus IS NOT NULL)
/

Oracle Server 8.1.7.3
IBM DYNIX/ptx Received on Fri Nov 07 2003 - 12:46:29 CST