| Bitmap
Indexes |
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| • | The most
common index type in Oracle DW environments |
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| – | Bitmap indexes
introduced in Oracle 7.3 |
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| – | Bitmap join
indexes introduced in Oracle9i |
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| – | Oracle has
over a dozen patents for bitmap index |
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| technology |
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| • | Oracle
provides patented compression technique for |
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| bitmap indexes |
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| – | Bitmap indexes
are 3-20x smaller than b-tree indexes |
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| – | Less storage
yields better query performance and more |
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| indexed
columns |
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