Method and apparatus for accessing multidimensional data

A method of reorganizing existing data in a multidimensional database, the method comprising:

• providing a multidimensional data storage model in which data is located in cells that are stored and retrieved in blocks, each block comprising one or more cells;
• providing a multidimensional logical access model independent of the multidimensional data storage model, the multidimensional logical access model comprising a tree index having one or more leaf nodes each corresponding with a cell and pointing to a block in the multidimensional data storage model containing the cell;
• gathering, by a computer system, historical data access information derived from a plurality of user queries of the multidimensional database, the gathered historical data access information comprising identifications of all existing cells that have been accessed and the number of times that each cell has been accessed;
• determining, by the computer system, for a first frequently-accessed cell, a second cell which is most frequently accessed along with the first frequently-accessed cell, using the gathered historical data access information;
• and
• reorganizing, by the computer system, one or more selected existing cells in the multidimensional data storage model by moving one or both of the first frequently-accessed and second cells into the same block irrespective of the data located therein to minimize the number of blocks retrieved to access cells required in response to a typical user query of the multidimensional database whereby the multidimensional data access model is optimized to respond to queries that are incongruent with the structure of the multidimensional logical access model.