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Home -> Community -> Mailing Lists -> Oracle-L -> RE: SOME SOLUTIONS!
are you going from an in-memory sort to a disk sort?
try doubling your sort_area_size (alter session set sort_area_size = XX;) and re-running
Kevin
-----Original Message-----
Sent: Thursday, August 08, 2002 11:44 AM
To: Multiple recipients of list ORACLE-L
Okay,
Just going from #1 query to #2 query went from subsecond response to 6 secs. Not to mention for each sum it gets progressively worse!!!. The explain plan is exactly the same and I ran the sort query below and no rows returned.
rem truncate table plan_table;
set timing on;
rem explain plan set statement_id='RON' for
select
/*+ INDEX(mv_birthstat,ndx_mvyr) */
brth_mthr_res_newco_code County,count(*),
-- sum(cert_chld_brth_year) Num1
--sum(decode(greatest(cert_chld_brth_year,1996),
least(cert_chld_brth_year,1998
), 1, 0)) / 3 Num2,
--sum(decode(greatest(cert_chld_brth_year,1997),
least(cert_chld_brth_year,1999
), 1, 0)) / 3 Num3
from mv_birthstat
where cert_chld_brth_year between '1995' and '1999'
and brth_mthr_res_state_code='10' and brth_mthr_age between 15 and 41 group by brth_mthr_res_newco_code;
/*+ INDEX(mv_birthstat,ndx_mvyr) */
brth_mthr_res_newco_code County,
sum(cert_chld_brth_year) Num1
--sum(decode(greatest(cert_chld_brth_year,1996),
least(cert_chld_brth_year,1998
), 1, 0)) / 3 Num2,
--sum(decode(greatest(cert_chld_brth_year,1997),
least(cert_chld_brth_year,1999
), 1, 0)) / 3 Num3
from mv_birthstat
where cert_chld_brth_year between '1995' and '1999'
and brth_mthr_res_state_code='10' and brth_mthr_age between 15 and 41 group by brth_mthr_res_newco_code; WHY WHY WHY WHY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!-----Original Message-----
Paula,
Sorry to join this thread late, if I am rehashing just igonre.
I notice that your 'numbers' are surrounded by quotes, which will implicitly disable the index on those columns, perhaps the cause of the index hint. Are those columns text or numbers? If numbers, take out the quotes (and perhaps the hint) and rerun query.
Also, your aggregate functions will cause sorting - are you sorting to disk? See the query at the end of this to find out. If so, perhaps a larger sort_area_size and sort_area_retained_size might be in order.
Again, ignore if redundant.
Run this to look at sorting:
select t1.tablespace
, extents
, sum( t1.blocks * to_number( t3.value ) ) / 1024 /
1024 mb_used
, sum( t1.extents ) tot_extents
, t2.username
, t2.osuser
, t2.SID ||','|| t2.serial# SID_PID
, t4.spid
, t5.sql_text
, t1.segtype
from
v$sort_usage t1
,v$session t2
,v$parameter t3
,v$process t4
,v$sqlarea t5
where t1.SESSION_ADDR = t2.SADDR
and t3.name = 'db_block_size'
and (t2.PROCESS=t4.SPID or t2.paddr = t4.addr)
and t2.sql_address=t5.address
and t2.status = 'ACTIVE'
group by
t1.tablespace
, t2.username
, t2.osuser
, t2.machine
, t2.schemaname
, t2.program
, t2.SID ||','|| t2.serial#
, t4.spid
, t5.sql_text
, t1.segtype
, segfile#
, extents
/
hth,
Jack
> ----
> | Operation | Name | Rows |
> Bytes| Cost | Pstart|
> Pstop |
>
----------------------------------------------------------------------------
> ----
> | SELECT STATEMENT | | 1 |
> 5 | 9331 | |
> |
> | SORT AGGREGATE | | 1 |
> 5 | | |
> |
> | SORT AGGREGATE | | 1 |
> 5 | | |
> |
> | INLIST ITERATOR | | |
> | | |
> |
> | PARTITION RANGE ITERAT| | |
> | |KEY(I)
> |KEY(I) |
> | BITMAP CONVERSION COU| | |
> | | |
> |
> | BITMAP INDEX RANGE S|NDX_MVYRS | |
> | |KEY(I)
> |KEY(I) |
>
> Cost higher but less than a second.
>
> Ignore the cost - higher cost was sign.
> Faster!!!!!Does Key(*) mean it is
> doing part. Elimin. I think so but can you see the
> inlist?
>
> Very fast with all years involved. Then added
> predicate:
>
> select
> /*+ INDEX(mv_birthstat,ndx_mvyrstatecoage) */
> count(*) from mv_birthstat
> where cert_chld_brth_year
> in('1995','1996','1997','1998','1999')
> and brth_MTHR_res_STATE_CODE = '10';
>
> - snails crawl by just adding the additional
> column!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
>
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com <http://www.orafaq.com> -- Author: Jack Silvey INET: jack_silvey_at_yahoo.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Toepke, Kevin M INET: ktoepke_at_trilegiant.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Thu Aug 08 2002 - 11:43:34 CDT
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