It is difficult to imagine data analysis without OLAP (On-Line Analytical Processing) technology. Although there are differing opinions about whether OLAP should be considered a technology or ideology. After all, OLAP can be imagined as a complex multi-dimensional cube, and as ordinary cross-tables ...

On-the-fly data aggregation of "flat" database tables is one of the first tasks faced by information system developers and their users. At the same time it is usually difficult to foresee the user needs in terms of data selection criteria (filters), dimensions in which the data needs to be aggregate...