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cbo performances

  • Report Performance with Bind Variable Updated:10-11

    Getting some very odd behaviour with a report in APEX v I have a complex query that takes 5 seconds to return via TOAD, but takes from 5 to 10 minutes in an APEX report. I've narrowed it down to one particular bind. If I hard code the dat

  • Disc Report Performance Updated:10-11

    Hi Friends, I have two pc with same configuration/OS/discoverer version . These two machines are on same network and accessing same database. On one pc report comes in 2 min. where as on other pc it takes more than 15 min. to execute. is there any di

  • How to resolve most of the Oracle SQL , PL/SQL Performance issues with help of quick Checklist/guidelines ? Updated:10-11

    Please go thru below important checklist/guidelines to identify issue in any Perforamnce issue and resolution in no time. Checklist for Quick Performance  problem Resolution ·         get trace, code and other information for given PE case          

  • Performance issue on 1 SQL request Updated:10-11

    Hi, We have a performance problem. We have 2 systems. PRD and QAS (QAS is a copy of PRD as of September 2nd) SQL request is identical. table structures is identical. indexes are identical. views are identical DB stats have all been recalculated on bo

  • URGENT: Migrating from SQL to Oracle results in very poor performance! Updated:10-11

    *** IMPORTANT, NEED YOUR HELP *** Dear, I have a banking business solution from Windows/SQL Server 2000 to Sun Solaris/ORACLE 10g migrated. In the test environment everything was working fine. On the production system we have very poor DB performance

  • SQL Area Usage, Performance Problem Updated:10-11

    Hi, I'm a software engineer, not a DBA, with a lot of doubts about our production environment, but I think that I have found a problem at our production Database. At our development database when I execute the same SQL statement over than onces, I ca

  • Query rewrite by CBO Updated:10-11

    Hello, Some days back, I came across a blog entry in which author concluded that when a = b and b = c, oracle does not conclude as a = c. He also provided a test case to prove his point. The URL is [

  • CBO not picking correct indexes or doing Full Scans Updated:10-11

    Database version - OS : Solaris 5.8 Storage: SAN Application : PeopleSoft Financials DB size : 450 gb DB server : 12 CPU ( 900 Mghz each ), 36 GB RAM ASMM - sga_target_size = 5 gb Locally managed tablespaces - MANUAL - db_file_multiblock_rea

  • Performance Issue Updated:10-11

    Hi, I'm not sure I'm posting this question in the right place, but here is better than no where. We recently upgraded all our DB environments (in the last month) from 8.0.6 to and we took performance hit. SQL that used to do rather well is do

  • Is there any performance difference in the order of columns referencing index? Updated:10-11

    I wish to find out if there is any performance difference or efficiency in specifying those columns referencing index(es) first in the WHERE clause of SQL statements. That is, whether the order of columns referencing the index is important???. E.g. i

  • Bloom filter and performance Updated:10-11

    I have the following query: SELECT                  obst.obst_id obstructionId                ,oost.comment_clob CommentClob                ,chp1.ptcar_no StartPtcar                ,chp2.ptcar_no EndPtcar                ,oost.track_code Track        

  • RBO X CBO Updated:11-30

    Hi everybody. I would like to understand where what we are missing here. We have several installations running 10g, and it's default value for OPTIMIZER_MODE is ALL_ROWS. Well, if there are no statistcs for the application tables, the RDBMS uses by d

  • CBO picking incorrect indexes or doing Full Scans ( table/indexes) Updated:11-30

    Database version - OS : Solaris 5.8 Storage: SAN Application : PeopleSoft Financials DB size : 450 gb DB server : 12 CPU ( 900 Mghz each ), 36 GB RAM ASMM - sga_target_size = 5 gb Locally managed tablespaces - MANUAL - db_file_multiblock_rea

  • CBO calculates un acceptable cost while using index. Updated:11-30

    Hi, I was wondering to see the execution plan for both the case using index/without index. We are using oracle 10G( with RAC in production at O/S:- sun solaris 10. Java based application is running in this database. One of the sql query is

  • RBO vs CBO : Are you going to maintain RBO in DBMS? Updated:11-30

    Hello, Oracle? I'm facing many critics about the type of SQL optimization from customer. I'm still using RBO in application SQL because, sometimes, your automatic optimization (analyze) make the execution plan of performance-oriented SQL worse and th

  • RBO to CBO conversions Updated:11-30

    Hi, I need some help. My databases are running in RBO environment using oracle 8i, 9i. Now, because RBO being obsolete in oracle 10g and later releases. I want to switch to CBO. My databases are in production. I want to look at all the scenarios for

  • Query performance using distinct Updated:11-30

    Greetings! We're on Oracle 8.1.7, Solaris 2.8. I have a query that utilizes a different access path if I use the word distinct in the select from this view. Here is our query: SELECT DISTINCT SETID, VENDOR_ID, VENDOR_NAME_SHORT, AR_NUM, NAME1, ADDRES