Please Help Me !! Performance Yuning Problem

This is the first time I have posted anything to any newsgroup. I hope this is the appropriate place for this type of thing. If not, I appologize.

I am writing a query which is running much longer than I expect (need). I am hoping that somebody can spot a problem with the query or offer a suggestion as to how to tune it.

• This is a single table query.
• The table is appx 90,000,000 rows
• It is running on a 24 node SP2 machine.
• In order to help decifer the "sum(round((instr" selection I will attempt to put it here in english. The intent is to return a value of 1 from the round function if the value in the A.USOC field matches the quoted string. I have tested this and it works.
• This query runs for 12+ hours (in fact it has never finished). I guess it should run 1-2 hours.
• I am unable to modify the table in any way. No new columns, indexes, etc...

CREATE TABLE GET_COUNT
  PCTFREE 0
  PCTUSED 90
  STORAGE (INITIAL 1M NEXT 1M PCTINCREASE 0)   TABLESPACE XXX
  PARALLEL (DEGREE 2 INSTANCES 20)
  UNRECOVERABLE
AS
SELECT /*+ FULL(A) */

   A.ACCT_ID
  ,A.ACCT_SEQ_NO
  ,A.TEL_NO
  ,A.NTWK_ACC_EXTNSN
  ,SUM(ROUND((INSTR('ESX  PKQ  ',A.USOC,1,1)/6)+.4)) AAA
  ,SUM(ROUND((INSTR('NNK  NSD  ',A.USOC,1,1)/6)+.4)) BBB
  ,SUM(ROUND((INSTR('NSK  NLRX8',A.USOC,1,1)/6)+.4)) CCC
  ,SUM(ROUND((INSTR('ESC  NLRXR',A.USOC,1,1)/6)+.4)) DDD
  ,SUM(ROUND(INSTR('ESYBQ',A.USOC,1,1)*2)) EEE

 AND SUBSTR(A.TEL_NO,4,3) IN ('233','296','847','292','732','843',


                              '435','424','228','458','324','454',


                              '456','232','421','423','923','379'))


          OR
    (SUBSTR(A.TEL_NO,1,3) = '712'
 AND SUBSTR(A.TEL_NO,4,3) IN ('264','262'))
          OR

 AND SUBSTR(A.TEL_NO,4,3) IN ('452','388','427','771','568','442',


                              '348','425','638','287','636','472',

                              '289','364','785','378','384','761',

                              '457','645','485','689','398','288',

                              '776','394','632','204','478','683',

                              '282','723','466','778','533','428',

                              '635','639','445','424','775','284',

                              '637','567','634','772','366','286',

                              '281','426','646','684','459','421',

                              '474','648','625','476','458','432',


                              '455','456','836','538','868'))


          OR
    (SUBSTR(A.TEL_NO,1,3) = '602'
 AND SUBSTR(A.TEL_NO,4,3) IN ('374','675','388','386','671'))
          OR
    (SUBSTR(A.TEL_NO,1,3) = '605'
 AND SUBSTR(A.TEL_NO,4,3) IN ('578','892','787','269','296','563',


                              '983','347','997','368','648','456',

                              '255','425','772','256','326','743',


                              '642','584','987')))


GROUP BY A.ACCT_ID, A.ACCT_SEQ_NO, A.TEL_NO, A.NTWK_ACC_EXTNSN;