On the use of bit maps for multiple key retrieval

Abstract

The traditional file structures used to support fast response to complex user queries have been based on the inverted list organization, using either the pointer or bit string representation. In this paper, the use of bit maps for executing multiple key searches is studied. Bit maps turn out to be less precise inverted lists Where the inversion is kept for a quantization of attribute domains and the objects referenced are blocks of data records. The goal is to reduce the total number of I/O accesses required to execute a retrieval based on a Boolean qualification. An evaluation of the method is given for both storage space and expected retrieval time under simplified assumptions. Key Words and Phrases: Multiple key retrieval, inverted lists, bit strings, bit maps, Boolean queries, data base management. CR Categories: 3.70, 3.71, 3.73, 3.74, 4.33, 4.34