What Is an MDDB?
A multidimensional database, or MDDB, is a specialized storage facility that allows data to be pulled from a data warehouse or other data sources for storage in a matrix-like format. The process of building an MDDB summarizes the raw data; the data stored in the MDDB is thus said to be presummarized. The MDDB enables users to quickly retrieve multiple levels of presummarized data through a multidimensional view. An MDDB is not a SAS data file; instead of the traditional structure used for SAS tables, an MDDB stores its data as an NWAY cube and zero or more subcubes.
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