Partial-match retrieval for dynamic files using linear hashing with partial expansions
The average number of disk accesses required to perform primary-key retrieval in systems using linear hasing can be reduced by employing the technique of partial expansions. This scheme maintains a more uniform distribution of records amongst the pages of the database file, thus reducing the average length of overflow chains and hence the average query cost. In this paper, we analyse the cost benefits of using linear hashing with partial expansions for partial-match retrieval and show that this type of indexing is effective for use with partial-match retrieval on highly dynamic files.
KeywordsHome Page Average Cost File Size Split Pointer Query Type
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