Results 1 to 2 of 2
  1. #1
    Join Date
    Dec 2008
    Location
    Toronto, Canada
    Posts
    399

    Unanswered: pctfree and cluster indexes

    DB2 v8.2 on AIX 5.1 / DB2 v9.5 on AIX 6.5
    we have OLTP environment. And pctfree params in our tables are all =-1 (from syscat.indexes). When I read on pctfree in the documentation it is always used with cluster indexes and we do not use cluster indexes. So my questions are:

    - what does pctfree=-1 mean? (it's not in the documentation for some reason).
    - what value of pctfree for OLTP environment should be used? (range)
    - is it necessarely used with cluster indexes or can be used with regular indexes too?

    Thanks in advance
    DB2 9.5/9.7 on Unix/AIX 6.1/Linux

  2. #2
    Join Date
    Jun 2003
    Location
    Toronto, Canada
    Posts
    5,516
    Provided Answers: 1
    Quote Originally Posted by MarkhamDBA

    - what does pctfree=-1 mean? (it's not in the documentation for some reason).
    My guess would be that the value has not been specified when creating the index, and the default value is in effect.

    Quote Originally Posted by MarkhamDBA
    - what value of pctfree for OLTP environment should be used? (range)
    That obviously depends on the number of inserts and updates to the indexed columns. The more changes you are making to the index, the higer PCTFREE should be. On the other hand, if you don't determine the particular index to be a performance bottleneck, you should probably leave PCTFREE alone.

    Quote Originally Posted by MarkhamDBA
    - is it necessarely used with cluster indexes or can be used with regular indexes too?
    PCTFREE applies to any index.
    ---
    "It does not work" is not a valid problem statement.

Posting Permissions

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