Relational Online Analytical Processing (ROLAP)

What does Relational Online Analytical Processing (ROLAP) mean?

Relational online analytical processing (ROLAP) is a kind of online analytical processing (OLAP) that analyzes data using multidimensional data models. The difference between ROLAP and other OLAPs is that it accesses data that is stored in a relational database rather than from a multidimensional database, which is the one most commonly used in other OLAPs. It can also generate SQL queries to perform calculations when an end-user wishes to do so.

Techopedia explains Relational Online Analytical Processing (ROLAP)

ROLAP can handle large volumes of data. Although its use of a relational database means that it requires more processing time, it can be accessed by any SQL tool, and it does not have to be a tool specifically for OLAPs. Compared to multidimensional online analytical processing (MOLAP), ROLAP tools are much better at controlling non-aggregated facts such as textual descriptions.

In terms of disadvantages, the performance of a ROLAP depends on the data size; it can be slow when the data being processed is large and fast if otherwise. Athough any SQL tool can access ROLAP, it is limited by these tools because SQL statements do not meet all users' needs, especially when performing complex calculations.