RE: performance issue for a specific column selection

From: <babu.nagarajan_at_Cummins.com>
Date: Wed, 28 Sep 2005 10:24:48 -0500
Message-id: <OF5A39DDE9.1E16FE50-ON0525708A.00549B29-0525708A.0054AB59@notes.cummins.com>

also can you post the explain plan for the one w/o the hospital_id and the one with it..

Babu

                                                                                                                                        
                      Yasin Baskan                                                                                                      
                      <yasbs_at_kocbank.com        To:       raja4list_at_yahoo.com, oracle list <oracle-l_at_freelists.org>                     
                      .tr>                      cc:                                                                                     
                      Sent by:                  Subject:  RE: performance issue for a specific column selection                         
                      oracle-l-bounce_at_fr                                                                                                
                      eelists.org                                                                                                       
                                                                                                                                        
                                                                                                                                        
                      09/28/2005 05:51                                                                                                  
                      AM                                                                                                                
                      Please respond to                                                                                                 
                      yasbs

Can you send the create script for HSTAB, is it a table, view, materialized view, etc...?

From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of raja rao
Sent: Wednesday, September 28, 2005 1:37 PM To: oracle list
Subject: performance issue for a specific column selection

Hi All,

Can someone help me why a simple select is behaving strage:

select hospital_id,acct# from HSTAB where rownum=1;

This is almost taking 20 seconds to get the data. Where as teh same sql without hospital_id column is taking just less than a second.

select acct#,mr# ,admit_dt from ...
This is taking less than a second. The only problem is with the hospital_id column.

When I checked the wait events, the below are the waits:

  SID EVENT                          MODULE
----- ------------------------------ -----------------------------------
USERNAME           P1         P2         P3
---------- ---------- ---------- ----------
   73 direct path write              SQL*Plus
OPS$ORACLE        201       6365          7

my db_files param is 200. So this file is temp file the wait is happening on.

I already have DISK_ASYNCH_IO=TRUE .

What else i have to do to fix this issue.

Thanks in advance,
Raj

Yahoo! for Good
Click here to donate to the Hurricane Katrina relief effort.

This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email

                                                 
                                                 
                                                 
 Bu mesaj ve onunla iletilen tum ekler

gonderildigi kisi ya da kuruma ozel ve Bankalar Kanunu geregince, gizlilik yukumlulugu tasiyor olabilir. Bu mesaj, hicbir sekilde, herhangi

 bir amac icin cogaltilamaz, yayinlanamaz ve     
 para karsiligi satilamaz; mesajin yetkili       
 alicisi veya alicisina iletmekten sorumlu kisi  
 degilseniz, mesaj icerigini ya da eklerini      
 kopyalamayiniz, yayinlamayiniz, baska kisilere  
 yonlendirmeyiniz ve mesaji gonderen kisiyi

derhal uyararak bu mesaji siliniz. Bu mesajin iceriginde ya da eklerinde yer alan bilgilerin dogrulugu, butunlugu ve guncelligi Bankamiz tarafindan garanti edilmemektedir ve bilinen viruslere karsi kontrolleri yapilmis olarak yollanan mesajin sisteminizde yaratabilecegi

 zararlardan Bankamiz sorumlu tutulamaz.         
                                                 

                                                                                                                    
 This message and the files attached to it are under the privacy liability in accordance with the Banking Law and   
 confidential to the use of the individual or entity to whom they are addressed. This message cannot be copied,     
 disclosed or sold monetary consideration for any purpose. If you are not the intended recipient of this message,   
 you should not copy, distribute, disclose or forward the information that exists in the content and in the         
 attachments of this message; please notify the sender immediately and delete all copies of this message. Our Bank  
 does not warrant the accuracy, integrity and currency of the information transmitted with this message. This       
 message has been detected for all known computer viruses thence our Bank is not liable for the occurrence of any   
 system corruption caused by this message

This e-mail transmission and any attachments to it are intended solely for the use of the individual or entity to whom it is addressed and may contain confidential and privileged information. If you are not the intended recipient, your use, forwarding, printing, storing, disseminating, distribution, or copying of this communication is prohibited. If you received this communication in error, please notify the sender immediately by replying to this message and delete it from your computer.

--
http://www.freelists.org/webpage/oracle-l

Received on Wed Sep 28 2005 - 10:27:12 CDT