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      • 90. Re: corrupted indexes
        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
          • 92. Re: corrupted indexes
            Hemant K Chitale
            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
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