The organization of data, e.g. a dimension, into a outline or logical tree structure. The strata of a hierarchy are referred to as levels. The individual elements within a level are referred to as categories. The next lower level in a hierarchy is the child; the next higher level containing the children is their parent.


Hybrid Online Analytical Processing. An approach to analytical processing that combines both MOLAP and ROLAP techniques.

Hardware Node

A computer on a network; for example, clients and servers.

Help Desk

A support system designed to assist end users with technical and functional questions and problems.


Two or more data elements having the same name but containing different data.