ROLAP (Relational Online Analytical Processing) uses multidimensional data models to analyze data, and does not require the pre-computation and storage of information. ROLAP tools access the data in a relational database and generate SQL queries to calculate information.
Advantages of ROLAP include:
Considered to be more scalable in handling large data volumes
Faster loading than the automated MOLAP loads
Data is stored in a standard relational database and can be accessed by any SQL reporting tool
Tools are better at handling non-aggregatable facts
Possibility to successfully model data that would not fit into a strict dimensional model
Leverages database authorization controls