Performance evaluation study of data retrieval in data warehouse environment

In recent years, data warehouse (DW) systems have become more important for decision making processes. This was due to the fact that they are capable of enhancing the value of an organization. DW used for storing large amount of data and making it available for decision makers and business analyst to make queries, analysis and planning without considering data changes in the operational database. In general, these quires are complex and consist of join operations and complex functions such as group by and order by which make execution takes so long. In addition, most of the information requests include dynamic ad hoc queries, which mean submitting any question at any time that might be run on very large data volumes. These could lead to have long running queries which causes server and application to run slowly and lack the accessibility where the ability to execute queries quickly and efficiently is a critical issue. As a result, one of the most important requirements of data warehouse server that should be considered is query performance. The purpose of this paper is to improve data warehouse performance by enhancing query response time. After an intensive review of previous studies and literature, techniques to improve data warehouse performance have been proposed.