Access path: Bitmap index

From: Raj Mareddi <yoursraju007_at_gmail.com>
Date: Tue, 18 Dec 2007 13:49:28 -0500
Message-ID: <7f411f4e0712181049s3273ba63j9ba51fc9c05717b9@mail.gmail.com>

  Index: INDEX1 Col#: 1 2
    LVLS: 2 #LB: 11825 #DK: 7478026 LB/K: 1.00 DB/K: 1.00 CLUF: 954385.00
  Index: INDEX2 Col#: 1
    LVLS: 1 #LB: 140 #DK: 1572 LB/K: 1.00 DB/K: 1.00 CLUF: 1655.00 SINGLE TABLE ACCESS PATH
  Column (#1): NAME (VARCHAR2)
    AvgLen: 6.00 NDV: 1557 Nulls: 0 Density: 6.4226e-04   Table: TAB1 Alias: TAB1
    Card: Original: 7388103 Rounded: 4745 Computed: 4745.09 Non Adjusted: 4745.09
  Access Path: TableScan
    Cost: 27120.03 Resp: 27120.03 Degree: 0

      Cost_io: 24677.00  Cost_cpu: 3763177144
      Resp_io: 24677.00  Resp_cpu: 3763177144
  Access Path: index (RangeScan)

    Index: INDEX1
    resc_io: 623.00 resc_cpu: 21679564
    ix_sel: 6.4226e-04 ix_sel_with_filters: 6.4226e-04     Cost: 637.07 Resp: 637.07 Degree: 1

trying bitmap/domain indexes ****** Access Path: index (AllEqRange) Index: INDEX2 resc_io: 1.00 resc_cpu: 10993 ix_sel: 6.4226e-04 ix_sel_with_filters: 6.4226e-04 Cost: 1.01 Resp: 1.01 Degree: 0 Access path: Bitmap index - rejected Cost: 1038.15 Cost_io: 1021.87 Cost_cpu: 25073088 Sel: 6.4226e-04 Not believed to be index-only Best:: AccessPath: IndexRange Index: INDEX1 Cost: 637.07 Degree: 1 Resp: 637.07 Card: 4745.09 Bytes: 0

Why is my bitmap index path rejected ?

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Received on Tue Dec 18 2007 - 12:49:28 CST

Access path: Bitmap index - rejected