How to optimize the mentioned SQL Query

Question

Hi,
I have a query like this:
SELECT XYZ.B1, XYZ.B2 FROM
SELECT * from A where ( A.C1 IN ( 0,1,2,3,4 ) ) AND ( A.C2 IN ( 1,2 ) )
AND (( A.C3 =15 ) and (A.C4 = 0 or A.C5 = 0)) AND A.C6 >= TO_DATE('2002-01-01
06:30:00', 'YYYY-MM-DD HH24:MI:SS') AND A.CP < 376137 ORDER BY A.CP DESC) XYZ
WHERE ROWNUM < 602
WHERE A.CP is the primary key and also the primary indexing is on that A.CP.
I have around 4 lakhs record in the Table A. The query is taking more than
2 minutes to execute on my m/c.
My basic requirement is to read last 602 records from A with CP less than
376137 plus matching other criteria mentioned in the query. It will be highly
grateful if someone provides with a much optimal query to perform the task.
TIA,
Tuhin

Answer 1

Hi John,
Thanks for the Response.
Below is explain plan you have asked for.
select AlmEvtTbl.AlmEvtId, AlmEvtTbl.AlmType, AlmEvtTbl.ComponentId,
          AlmEvtTbl.TimeStamp, AlmEvtTbl.Severity, AlmEvtTbl.State,
AlmEvtTbl.Category,          AlmEvtTbl.CauseType, AlmEvtTbl.CauseCode,
AlmEvtTbl.UnitType, AlmEvtTbl.UnitId,          AlmEvtTbl.UnitName,
AlmEvtTbl.ServerName, AlmEvtTbl.StrParam, AlmEvtTbl.ParentCustId,
          AlmEvtTbl.ExtraParam1, AlmEvtTbl.ExtraParam2, AlmEvtTbl.ExtraParam3,
AlmEvtTbl.ExtraStrParam, AlmEvtTbl.SrcIPAddress,          AlmEvtTbl.DestIPAddress,
AlmEvtTbl.DestPort, AlmEvtTbl.SessionDir,           AlmEvtTbl.CustomerId,
AlmEvtTbl.ProfileId, AlmEvtTbl.ParentProfileId, AlmEvtTbl.CustomerName
from
(select AlmEvtSysPeView.* from AlmEvtSysPeView where (
AlmEvtSysPeView.Severity IN ( 0,1,2,3,4 ) ) and ( AlmEvtSysPeView.State
IN ( 1,2 ) ) and (( AlmEvtSysPeView.Category =3 or
AlmEvtSysPeView.Category =14 ) and (AlmEvtSysPeView.Customerid = 0 or
AlmEvtSysPeView.ParentCustId = 0)) and AlmEvtSysPeView.TimeStamp >=
TO_DATE('2002-01-01 06:30:00', 'YYYY-MM-DD HH24:MI:SS') and
AlmEvtSysPeView.AlmEvtId < 376137 order by AlmEvtSysPeView.almevtid desc)
almevttbl where rownum < 202
call count cpu elapsed disk query current rows
Parse 1 0.02 0.02 0 0 0 0
Execute 2 0.01 0.01 0 0 0 0
Fetch 2 7.61 85.03 19469 1848476 2153 201
total 5 7.64 85.06 19469 1848476 2153 201
Misses in library cache during parse: 1
Optimizer goal: CHOOSE
Parsing user id: 77 (SKAGARWAL)
Rows Row Source Operation
201 COUNT STOPKEY
201 VIEW
201 SORT ORDER BY STOPKEY
306899 NESTED LOOPS OUTER
306900 NESTED LOOPS OUTER
306900 TABLE ACCESS BY INDEX ROWID ALMEVTTBL
374210 INDEX RANGE SCAN (object id 205151)
306899 INDEX UNIQUE SCAN (object id 205144)
306899 TABLE ACCESS BY INDEX ROWID ALMEVTPETBL
613798 INDEX UNIQUE SCAN (object id 205146)
Rows Execution Plan
0 SELECT STATEMENT GOAL: CHOOSE
201 COUNT (STOPKEY)
201 VIEW
201 SORT (ORDER BY STOPKEY)
306899 NESTED LOOPS (OUTER)
306900 NESTED LOOPS (OUTER)
306900 TABLE ACCESS (BY INDEX ROWID) OF 'ALMEVTTBL'
374210 INDEX (RANGE SCAN) OF 'ALMEVTTBL_PK' (UNIQUE)
306899 INDEX (UNIQUE SCAN) OF 'ALMEVTIDSURLTBL_PK' (UNIQUE)
306899 TABLE ACCESS (BY INDEX ROWID) OF 'ALMEVTPETBL'
613798 INDEX (UNIQUE SCAN) OF 'ALMEVTPETBL_PK' (UNIQUE)
Thanks,
Tuhin
Hi Tuhin,
You haven't posted the EXPLAIN PLAN for the query -
that would be useful.
400,000 records isn't a lot and 2 minuets seems a
long time.
The first thing I'd try is creating (and analysing)
an index on C6 - see if that helps.
d.