Please help in query performance

Question

select bg.billing_group_id,r.rating_result, count(*),rc.source,rc.description
from rejected_record r,
result_code@RD rc,
terminal_device@cust td,
personal_account_td@cust patd,
personal_account@cust pa,
billing_group@cust bg,
-- tariff_plan@rd tp,
(select pcs.primary_session_id, pcs.charging_date
from pcs@umr_interface
where pcs.range_cdr_file_source not like 'HOT%'
--and lower(pcs.RANGE_CDR_FILE_SOURCE) not like 'rec%'
-- and lower(pcs.RANGE_CDR_FILE_SOURCE) not like 'sms%'
-- and lower(pcs.RANGE_CDR_FILE_SOURCE) not like 'data%'
-- and pcs.CHARGING_TYPE_ID = 1
and pcs.charging_date between '20/Aug/2010' and '21/Sep/2010') t
where r.primary_session_id = t.primary_session_id
and rc.code (+)= r.rating_result
and td.terminal_device_id = patd.terminal_device_id
and patd.personal_account_id = pa.personal_account_id
and r.calling_party_number_rid = td.msisdn
and pa.billing_group_id = bg.billing_group_id
and r.is_precharged=0
--and td.tariff_plan_id=tp.tariff_plan_id
and (nvl(td.date_to,'01.01.2000')='01.01.2000')
and (nvl(pa.date_to,'01.01.2000')='01.01.2000')
and (nvl(patd.date_to,'01.01.2000')='01.01.2000')
group by r.rating_result, rc.source, rc.description,bg.billing_group_id
order by r.rating_result
SQL> select * from v$version;
BANNER
Oracle9i Enterprise Edition Release 9.2.0.8.0 - 64bit Production
PL/SQL Release 9.2.0.8.0 - Production
CORE     9.2.0.8.0     Production
TNS for Solaris: Version 9.2.0.8.0 - Production
NLSRTL Version 9.2.0.8.0 - Production
SQL>
Above select query took only 10 mins when those nvl functions where not there..
but when these nvl fuctions are added this takes lot of time....
please help to optimce it..
first i tried with is null.. it took lot of time.. ten i replaced it with nvl function...
please somebody help to optimize this query

Answer 1

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