Solutions for improving data extraction from virtual data warehouses

The data warehousing project’s team is always confronted with low performance in data extraction. In a Business Intelligence environment this problem can be critical because the data displayed are no longer available for taking decisions, so the project can be compromised. In this case there are several techniques that can be applied to reduce queries’ execution time and to improve the performance of the BI analyses and reports. Some of the techniques that can be applied to reduce the cost of execution for improving query performance in BI systems will be presented in this paper.