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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Long-running SQL
Stephane,
Thanks for your reply.
I am going to check into setting the nulls with the application owner to see if that is an acceptable solution.
I am unable to create a function-based index as this is a version 8.0.4 database.
Thanks,
Cherie
Stephane
Faroult To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
<sfaroult_at_orio cc:
le.com> Subject: Re: Long-running SQL
Sent by:
root_at_fatcity.c
om
03/27/02 03:03
PM
Please respond
to ORACLE-L
Cherie_Machler_at_gelco.com wrote:
>
> We have a statement that I feel takes too long to run in a nightly data
> load.
> The table it runs against has 386,000 records. It runs for about 10
> seconds
> on average. We're only loading about 50,000 records a night but this
> statement
> is running during the majority of the 9-hour load time. This is causing
> the
> load to run longer than our allowable window and causing me untold
> headaches.
> If anyone has any suggestions to make this run faster, I'd be greatly
> appreciative.
>
> The columns in the where statement are all part of an index. However,
> the functions on the columns add additional execution time and
complexity.
>
> This is an 8.0.4 database so I can not make this a function-based index.
>
> I put this in a couple of SQL tuning tools and came up with no valid
> alternatives.
> I can't help thinking that the statement could be rewritten into a couple
> of statements
> so that it would be more efficient. However, I'm not skilled enough
with
> SQL to
> do it. Perhaps someone else is. Here's the code.
>
> SELECT /*+ INDEX(EXP_COST_CENTER_DIM EXP_COST_CENTER_DIM_IDX1) + */
> EXP_COST_CENTER_KEY
> FROM EXP_COST_CENTER_DIM
>
> WHERE ACCOUNT_NUMBER = :b1 AND
> NVL(ORG_LEVEL_1_VALUE,'NONE') = NVL(:b2,'NONE') AND
> NVL(ORG_LEVEL_2_VALUE,'NONE') = NVL(:b3,'NONE') AND
> NVL(ORG_LEVEL_3_VALUE,'NONE') = NVL(:b4,'NONE') AND
> NVL(ORG_LEVEL_4_VALUE,'NONE') = NVL(:b5,'NONE') AND
> NVL(ORG_LEVEL_5_VALUE,'NONE') = NVL(:b6,'NONE') AND
> NVL(ORG_LEVEL_6_VALUE,'NONE') = NVL(:b7,'NONE') AND
> NVL(ORG_LEVEL_7_VALUE,'NONE') = NVL(:b8,'NONE') AND
> NVL(ORG_LEVEL_8_VALUE, 'NONE')= NVL(:b9,'NONE') AND
> ROWNUM = 1
>
> SQL> desc exp_cost_center_dim
> Name Null? Type
> ------------------------------- -------- ----
> EXP_COST_CENTER_KEY NOT NULL NUMBER(7)
> ACCOUNT_NUMBER NOT NULL NUMBER(9)
> BATCH_WINDOW_DATE_KEY NOT NULL NUMBER(5)
> ORG_LEVEL_1_VALUE VARCHAR2(20)
> ORG_LEVEL_2_VALUE VARCHAR2(20)
> ORG_LEVEL_3_VALUE VARCHAR2(20)
> ORG_LEVEL_4_VALUE VARCHAR2(20)
> ORG_LEVEL_5_VALUE VARCHAR2(20)
> ORG_LEVEL_6_VALUE VARCHAR2(20)
> ORG_LEVEL_7_VALUE VARCHAR2(20)
> ORG_LEVEL_8_VALUE VARCHAR2(20)
> DATA_SOURCE_MOD_DATETIME NOT NULL DATE
> DATA_WAREHOUSE_MOD_DATETIME NOT NULL DATE
> DATA_MART_MOD_DATETIME NOT NULL DATE
>
> SQL> select column_name from dba_ind_columns where index_name
> ='EXP_COST_CENTER_D
> IM_IDX1';
>
> COLUMN_NAME
>
> ACCOUNT_NUMBER
> ORG_LEVEL_1_VALUE
> ORG_LEVEL_2_VALUE
> ORG_LEVEL_3_VALUE
> ORG_LEVEL_4_VALUE
> ORG_LEVEL_5_VALUE
> ORG_LEVEL_6_VALUE
> ORG_LEVEL_7_VALUE
> ORG_LEVEL_8_VALUE
>
> SQL> select column_name from dba_ind_columns where index_name
> ='EXP_COST_CENTER_D
> IM_PK';
>
> COLUMN_NAME
>
> EXP_COST_CENTER_KEY
>
> Thanks,
>
> Cherie Machler
> Oracle DBA
> Gelco Information Network
>
Cherie,
I have only seen pieces of what I was expecting, so I am stepping in
somewhat belatedly :
o as several people underlined, your NVL functions are performance
killers. Basically, the only usable column in your concatenated index
happens to be ACCOUNT_NUMBER. Whether Oracle decides or not to use it is
not very relevant, the point is that it's a rather useless index for
this query.
o I see two ways out :
-- HTH, Stephane Faroult Oriole Software -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Stephane Faroult INET: sfaroult_at_oriole.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: INET: Cherie_Machler_at_gelco.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 Mar 28 2002 - 08:23:26 CST
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