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  • 90. Re: corrupted indexes
    635471 Expert
    Currently Being Moderated
    burleson wrote:
    It sounds like Hemant has been crippled by bitmap freelists (ASSM), a feature that was never intended for high-volume production databases:

    Slow for full-table scans — Several studies have shown that large-table full-table scans (FTS) will run longer with ASSM than standard bitmaps. ASSM-FTS tablespaces are consistently slower than Freelist-FTS operations. This implies that ASSM may not be appropriate for decision support systems and warehouse applications, unless partitioning is used with Oracle Parallel Query.
    Do you have a reference for these studies?
  • 91. Re: corrupted indexes
    userxyz1234 Explorer
    Currently Being Moderated
    deleted
  • 92. Re: corrupted indexes
    Hemant K Chitale Oracle ACE
    Currently Being Moderated
    UPDATE BY HEMANT K CHITALE (the same person !)

    I understand that Burleson has quoted this posting of mine, quite out of context at in his article on [Online Index Rebuilding.|http://www.dba-oracle.com/t_scheduling_oracle_index_rebuilding.htm]


    NOTE : I do not recommend rebuilding of ALL indexes weekly. This was a specific table (and I have identified only three such likely tables in a database of thousands of tables) that may require : Preferably a COALECE (as adviced by Jonathan Lewis) -- if I can get the code changed !! -- or, as the second best option, a regular REBUILD.

    The behaviour described in Oracle Bug#6447841 matches what I have seen. This is [clear later in this same thread|http://forums.oracle.com/forums/thread.jspa?messageID=3792540#3792540]


    Here are two postings on my blog where I discuss Rebuilding Indexes -- in general, not relating to the behaviour described in Bug 6447841.

    [1. Rebuilding Indexes|http://hemantoracledba.blogspot.com/2008/03/rebuilding-indexes.html]
    [2. Rebuilding Indexes - When and Why ?|http://hemantoracledba.blogspot.com/2008/03/rebuild-indexes-when-and-why.html]


    Hemant K Chitale
    http://hemantoracledba.blogpsot.com
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