# Dimensional Data Modeling - OLAP Cube

### Table of Contents

## 1 - About

An OLAP cube is a dimensional data structure that answer dimensional query. It store data in a multidimensional way. You can a cube as an extension of the two dimensions relational table.

## 2 - Articles Related

## 3 - Creation

A cube is defined:

- its dimension (and hierarchy)
- and measures (calculation)

and is generally pre-computed.

## 4 - Computation

The OLAP cube consists of numeric facts called measures which are categorized by dimensions. The cube metadata may be created from a star schema or snowflake_schema of tables in a relational database. Measures are derived from the records in the fact table and dimensions are derived from the dimension tables.