发明名称 |
Compressibility estimation of non-unique indexes in a database management system |
摘要 |
A method, information processing system, and computer readable storage product estimate a compression factor. A set of key values within an index are analyzed. Each key value is associated with a record identifier (“RID”) list comprising a set of RIDs. The index is in an uncompressed format and includes a total byte length. A number of RIDs associated with each key value is estimated for each key value in the set of key values. A total byte length for all RID deltas between each at least two consecutive RIDs within a RID list is estimated for each RID list based on the number of RIDs that have been determined. The total byte length estimated for each RID list is accumulated. A compression factor associated with the index is determined by dividing the total byte length that has been accumulated by the byte length of the index.
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申请公布号 |
US7895171(B2) |
申请公布日期 |
2011.02.22 |
申请号 |
US20080057055 |
申请日期 |
2008.03.27 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
BHATTACHARJEE BISHWARANJAN;LIM LIPYEOW;MIHAILA GEORGE A. |
分类号 |
G06F17/30 |
主分类号 |
G06F17/30 |
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