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focuses on :

1. Know What’s Cube?

1-1 Cube concept

In BI field, Cube is a very important concept, which is the short name of multidimensional Cube. It is mainly used to support OLAP (On-Line Analytical Processing) and provide support for enterprise decision making. A Cube is like a coordinate system, and each Dimension represents an axis. To obtain a point, you must obtain a value on each axis, and this point is the Cell in the Cube.

1-2 Cube is introduced

Cube is the key to online analysis

They are a multidimensional structure that includes raw factual data, aggregated data, and aggregated data that allows users to quickly perform complex queries.

Cube contains two basic concepts

1. The dimension

2. To measure the

Dimension:

Dimensions provide a categorical description, representing a class of analytical perspectives through which users analyze metrics. Take the three dimensions in the figure above: time, product, and region

Measures:

Metrics represent numerical information used to aggregate analysis, and the collection of measures is combined into a particular dimension. Such as quantity, sales volume, etc.

Levels: A hierarchy that can be contained on a dimension, representing a specific taxonomy. As shown in the figure above, the regional dimension can contain levels: country, province and city; The time dimension contains levels that include: year, quarter, month, day, etc.

A member, one of the most important concepts, is the item value on a dimension (including the measure

). For example, in the time dimension above, the members of “year” level include: 2000,2001,2002,2003… Monthly members include: 1, 2, 3, etc.

A computed member is a member that runs dynamically computed through a special representation. That is the result of Measures. Calculated members do not affect existing Cube data and can create complex expressions based on Cube data through a variety of mathematical expressions and a variety of function definitions. Any dynamic analysis function can be realized by calculating members, such as the implementation of the ratio, the period ratio, and so on.