A system and method for improving a query on a relational database in a business intelligence system is provided. A multidimensional data table is provided in the database. A sampling dimension is appended to the data table. The sampling dimension includes a number of cells, and wherein each cell includes a sampling value corresponding to the data of at least one of the dimensions of the data table. The data table is then clustered in at least one of the dimensions based on the associated sampling value in the sampling dimension. A query for a subset of data can then be executed on the clustered data table based on the sampling values.