How to reduce this query execution time !

Question

Just use your original cursor as an inline view, like so:
CREATE OR REPLACE PROCEDURE SP_TEST_audit_history2
(p_start IN date,
p_end IN date,
p_msgcode IN varchar2,
p_partnername IN varchar2,
p_status IN varchar2,
p_locationname IN varchar2,
p_custbusunit IN varchar2,
p_sysaudithistory_cur OUT plutotypes.ref_cursor,
p_status1 OUT NUMBER)
AS
BEGIN
OPEN p_sysaudithistory_cur
FOR
SELECT tfm.hubmsgid,
tfm.status || '-'|| nvl2 (tfm.exception_id, 'FAILED', 'OK'),
tfm.datetime,
tfm.exception_id
FROM tfm_status tfm,
(SELECT DISTINCT MAX (tfm.datetime) datetime, tfm.hubmsgid
FROM tfm_status tfm, vw_msgcode_part_locn vw
WHERE tfm.datetime >= NVL (p_start, TO_DATE ('01/01/1981', 'DD/MM/YYYY'))
AND tfm.datetime <= NVL (p_end, TO_DATE ('31/12/9999','DD/MM/YYYY'))
AND tfm.msgcode LIKE NVL (p_msgcode, '%')
AND vw.msgcode = tfm.msgcode
AND vw.partnername LIKE NVL (p_partnername, '%')
AND tfm.status LIKE NVL (p_status, '%')
AND vw.locationname LIKE NVL (p_locationname, '%')
AND vw.custbusunit LIKE NVL (p_custbusunit, '%')
AND rownum < 250
GROUP BY tfm.hubmsgid) c_hubmsgids
WHERE tfm.hubmsgid = c_hubmsgids.hubmsgid /* here only i am getting error*/
AND tfm.datetime = c_hubmsgids.datetime
AND tfm.status like NVL (p_status, '%');
p_status1 := 0;
EXCEPTION
WHEN NO_DATA_FOUND THEN p_status1 := 1;
END SP_TEST_audit_history2;
If i run this query it is taking 18 seconds to retrive the records becoz of that group by clause..
Can any body suggest any changed in code ( any hints) to make it faster that is execution time will be less than 10 seconds
Thanx in advance
prasanth a.s.

Answer 1

Try removing the word distinct and see if that helps. Distinct should not be needed since the max and group by will result in distinct values.