Storage modes in SQL Server Analysis Services

Cube data divided into meta data, detail data and aggregated data.

ROLAP stands for Relational Online Analytical Processing,
Cube only  builds model. Its having only meta data. Detail and aggregated data in relational database.

MOLAP stands for Multidimensional OLAP,  Cube with meta data, detailed data and aggregated data.
HOLAP stands for Hybrid OLAP, Cube with meta data and aggregated data. Detail data in relational database.

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