horizontal fragmentation as a technique to improve the performance of drill-down and roll-up queries
In this paper, we focus on the horizontal fragmentation of data warehouses. Our main contribution is the proposal of the MHF-DHA algorithm, which is aimed at improving the performance of drill-down and roll-up queries by horizontally fragmenting data warehouses organized in different levels of aggregation. Besides allowing that multiple dimensions be used as a basis for the fragmentation, the algorithm also explores the hierarchical structure of these dimensions. The performance tests carried out using the TPC-H benchmark showed that the proposed fragmentation provides a huge improvement on the query performance, with a reduction in elapsed time and disk accesses between 71\% and 99\%.
horizontal fragmentation drill-down and roll-up queries