What is an OLAP Cube?
OLAP
achieves the multidimensional functionality by using a structure called a cube. A cube is
a collection of numeric data organized by arrays of discrete identifiers. Cubes
were created to give a logical structure to the pivot table approach to
analyzing large amounts of numerical data. It is a storage structure used by
classic data warehousing products in place of many (often normalized) tables.
Rather than using tables with rows and columns, cubes use dimensions and measures
(or facts). Also, cubes will usually present data that is aggregated (usually
summed), rather than presenting each individual item (or row). The structure of
a cube is often described this way: cubes present a summarized, aggregated view
of enterprise data, as opposed to normalized table sources that present detailed
data. Cubes are populated with a read-only copy of source (or production) data.
In some cases, cubes contain a complete copy of production data; in other
cases, cubes contain subsets of source data. The data is moved from source
systems to the destination cubes via extract, transform, and load (ETL)
processes.
Creating an OLAP
Cube using BIDS, you need to perform these steps:
• Create a new
Analysis Services project
•
Define a data source
• Define a data
source view
• Invoke the Cube
Wizard