Multidimensional Online Analytical Processing (MOLAP) is a kind of online analytical processing (OLAP) that, like Relational Online Analytical Processing (ROLAP), uses a multidimensional data model to analyze data. Hybrid online analytical processing (HOLAP) is a combination of relational ROLAP and MOLAP.
In MOLAP, data is stored in a multidimensional semantic model. It has excellent performance and can do fast calculations.
In ROLAP, the data is stored in the relational database. It can handle large amounts of data and leverage functionalities inherent in the relational database. Query time can be longer if the underlying data size is large.
The difference between MOLAP and ROLAP is that MOLAP requires that information first be processed before it is indexed directly into a multidimensional semantic model, whereas ROLAP is entered directly into a relational database.
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