Sql query runing slow with lower cost

Question

Hello
I am working on Oracle 11g and AIX.I have one sql query which is ruing slow as reported by user.
When i am commenting few line of code it is runing fast.
I noticed that the execution plan cost of first query is less and second ...as cost of sccond qurey is more.But users are say it is runing fast.
How it can possiable ?
Any idea why second query is runing fast after commenting few columns in select and group by clause.
Query 1
SELECT PH.CTRL_NBR, PD.SEQ_NBR,PH.CNTRY,PH.SHIP_DATE, PHI.WAVE_NBR, PD.ID, PD.QTY,
IM.PACK_QTY,
IM.UNIT_VOL,
IM.PACK_QTY,
MAX(CD.PACK_QTY) AS CASE_QTY,
IM.UNIT_WT
FROM HDR PH,
HDR_INTRNL PHI,
DTL PD,
HDR CH,
CASEDTL CD,
IMASTER IM
WHERE PH.CTRL_NBR = PHI.CTRL_NBR
AND PD.CTRL_NBR = PH.CTRL_NBR
AND PD.QTY > 0
AND SUBSTR(CD.ID, 1, 9) = SUBSTR(PD.ID, 1, 9)
AND CD.CASENBR = CH.CASENBR
AND CH.STAT_CODE BETWEEN '10' AND '90'
AND IM.ID = PD.ID
AND PHI.WAVE_NBR='EL57893'
GROUP BY PH.CTRL_NBR, PD.SEQ_NBR, PH.CNTRY, PH.SHIP_DATE, PHI.WAVE_NBR, PD.ID, PD.QTY,
IM.PACK_QTY,
IM.UNITVOL,
IM.UNITWT,
IM.PACK_QTY
Query 2 .
SELECT PH.CTRL_NBR,
PD.SEQ_NBR,
PH.CNTRY,
PH.SHIP_DATE,
PHI.WAVE_NBR,
PD.ID,
PD.QTY,
-- IM.PACK_QTY,
-- IM.UNIT_VOL,
-- IM.PACK_QTY,
MAX(CD.PACK_QTY) AS CASE_QTY,
-- IM.UNIT_WT
FROM HDR PH,
HDR_INTRNL PHI,
DTL PD,
HDR CH,
CASEDTL CD,
IMASTER IM
WHERE PH.CTRL_NBR = PHI.CTRL_NBR
AND PD.CTRL_NBR = PH.CTRL_NBR
AND PD.QTY > 0
AND SUBSTR(CD.ID, 1, 9) = SUBSTR(PD.ID, 1, 9)
AND CD.CASENBR = CH.CASENBR
AND CH.STAT_CODE BETWEEN '10' AND '90'
AND IM.ID = PD.ID
AND PHI.WAVE_NBR='EL57893'
GROUP BY PH.CTRL_NBR, PD.SEQ_NBR, PH.CNTRY, PH.SHIP_DATE, PHI.WAVE_NBR, PD.ID, PD.QTY,
--IM.PACK_QTY,
--IM.UNITVOL,
--IM.UNITWT,
--IM.PACK_QTY
Edited by: oradba11 on Sep 6, 2012 2:11 PM
Edited by: oradba11 on Sep 6, 2012 2:12 PM

Answer 1

oradba11 wrote:
Hello
I am working on Oracle 11g and AIX.I have one sql query which is ruing slow as reported by user.
When i am commenting few line of code it is runing fast.
I noticed that the execution plan cost of first query is less and second ...as cost of sccond qurey is more.But users are say it is runing fast.
How it can possiable ? <snip>
This doesn't address your question, but let me suggest that for your own sanity you start brining some formatting to your sql. And for the sanity of those on this forum of whom you expect assistance, you preserve that formatting through the use of the code tags (see the FAQ for details).
I've done the first one for you, as an example of what I mean
SELECT
     PH.CTRL_NBR
,     PD.SEQ_NBR
,     PH.CNTRY
,     PH.SHIP_DATE
,     PHI.WAVE_NBR
,     PD.ID
,     PD.QTY
,     IM.PACK_QTY
,     IM.UNIT_VOL
,     IM.PACK_QTY
,     MAX(CD.PACK_QTY) AS CASE_QTY
,     IM.UNIT_WT
FROM
     HDR PH
,     HDR_INTRNL PHI
,     DTL PD
,     HDR CH
,     CASEDTL CD
,     IMASTER IM
WHERE
     PH.CTRL_NBR = PHI.CTRL_NBR
   AND  PD.CTRL_NBR = PH.CTRL_NBR
   AND  PD.QTY > 0
   AND  SUBSTR(CD.ID, 1, 9) = SUBSTR(PD.ID, 1, 9)
   AND  CD.CASENBR = CH.CASENBR
   AND  CH.STAT_CODE BETWEEN '10' AND '90'
   AND  IM.ID = PD.ID
   AND  PHI.WAVE_NBR='EL57893'
GROUP BY
     PH.CTRL_NBR
,     PD.SEQ_NBR
,     PH.CNTRY
,     PH.SHIP_DATE
,      PHI.WAVE_NBR
,      PD.ID
,      PD.QTY
,      IM.PACK_QTY
,     IM.UNITVOL
,     IM.UNITWT
,     IM.PACK_QTY