DBAsupport.com Forums - Powered by vBulletin
Results 1 to 8 of 8

Thread: Aanlyze Query

  1. #1
    Join Date
    Mar 2004
    Location
    India
    Posts
    11

    Aanlyze Query

    Dear Sir/Madam,
    I have recently joined as a junior DBA in a company.I am supposed to tune the database on which all the application on it are running very slow.
    I have gathered information from users and there problem and i want to start with SQL Tuning.

    Kindly clear my following doubts.


    I have few questions to ask.
    1. How I should start my work
    2. What exactly happens in Oracle Database when table is analyzed.
    3. Which table should be analyzed, the tables belonging to the schema in which application users are working or all?
    4. Whether column should also be analyzed.
    5. The statistics which we gather, are they one on which database should work on ?
    6. How can I compare the present statistics value to the value which has been changed?
    7. Do we need to shift from optimizer mode 'CHOOSE' to 'FIRST ROWS'.
    8. Do views also need to be analyzed?If yes, with which option estimate or compute.
    9. Will any users will face any problem while table will be analyzed.
    10. Which option I should choose to analyze tables,estimate or compute.
    11. Is 10% sample size is good for tables having rows more than 10000.
    12. How will I judge the results of analyzing the tables.
    13. At what interval tables should normally be analyzed.
    14. What should be my next step after analyzing the table in SQL Tuning.


    Regards,
    Saurabh

  2. #2
    Join Date
    Jan 2004
    Location
    Bangalore, India
    Posts
    66
    Dear Saurabh,
    I strongly advice you to go through the Oracle documentation first, before undertaking any performance tuning...
    It can have uncertain repurcussions, unless you can afford to throw away a hard day's work :-).

    Oracle documentation on performance (Oracle Performance Methods and Oracle Performance Guide and Reference) need to be studied, which answers all or most of ur questions.
    Once u r familiar with the basics, u can start experimenting with a test database.. All the best !

  3. #3
    Join Date
    Mar 2002
    Location
    Manchester, England
    Posts
    202
    performance tuning a production system seems a strange task to throw at a junior DBA

    You've got your work cut out

  4. #4
    Join Date
    Nov 2002
    Location
    Geneva Switzerland
    Posts
    3,142

    Re: Aanlyze Query

    Originally posted by saurabhvtechno
    1. How I should start my work
    Answer: If you don't have a test system, build one.

  5. #5
    Join Date
    Aug 2002
    Location
    Colorado Springs
    Posts
    5,253
    I would also check that the code is making proper use of bind variables -- if it isn't then that would be a prime cause of performance problems.
    David Aldridge,
    "The Oracle Sponge"

    Senior Manager, Business Intelligence Development
    XM Satellite Radio
    Washington, DC

    Oracle ACE

  6. #6
    Join Date
    Jan 2001
    Posts
    3,134
    Originally posted by slimdave
    I would also check that the code is making proper use of bind variables -- if it isn't then that would be a prime cause of performance problems.
    You want to elaborate on that one Dave, I'm interested.

    MH
    I remember when this place was cool.

  7. #7
    Join Date
    Aug 2002
    Location
    Colorado Springs
    Posts
    5,253
    David Aldridge,
    "The Oracle Sponge"

    Senior Manager, Business Intelligence Development
    XM Satellite Radio
    Washington, DC

    Oracle ACE

  8. #8
    Join Date
    Jan 2001
    Posts
    3,134
    Kool thanks!

    MH
    I remember when this place was cool.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


Click Here to Expand Forum to Full Width