Efficient Compression of Text Attributes of Data Warehouse Dimensions.

This paper proposes the compression of data in Relational Database Management Systems (RDBMS) using existing text compression algorithms. Although the technique proposed is general, we believe it is particularly advantageous for the compression of medium size and large dimension tables in data warehouses. In fact, dimensions usually have a high number of text attributes and a reduction in their size has a big impact in the execution time of queries that join dimensions with fact tables. In general, the high complexity and long execution time of most data warehouse queries make the compression of dimension text attributes (and possible text attributes that may exist in the fact table, such as false facts) an effective approach to speed up query response time. The proposed approach has been evaluated using the well-known TPC-H benchmark and the results show that speed improvements greater than 40% can be achieved for most of the queries. [ABSTRACT FROM AUTHOR]