Function Based Index
DBAsupport.com Forums - Powered by vBulletin
Results 1 to 3 of 3

Thread: Function Based Index

  1. #1
    Join Date
    Mar 2001
    Location
    New York , New York
    Posts
    577
    Hi,
    I have a function based index and a regular index on the same column of a table.

    I have a table which has a column

    date_of_story Date

    I have created a function based index on it as

    create index testme2 on news_story(trunc(date_of_story));

    also i have create another regular non unique index on the same column .

    what kind of effect will this have on performance.

    Thanks
    Ronnie

  2. #2
    Join Date
    Mar 2001
    Location
    New York , New York
    Posts
    577
    Still waiting

  3. #3
    Join Date
    Jan 2002
    Posts
    59
    When a query carries a where clause that is not simillar in all respects literelly, then the index is not used.
    Like , a table may have a normal index on column C1 and when used in querry C1='' then its fine, but
    if you use C1=truncate(), then here the index is not used.
    So, to over come that you would create the index based on your most application / query requirement.

    Thanx
    Sanjay

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