What is ROLAP?

ROLAP represents Relational OLAP. It can save the data based on the familiar relational DBMS technology. In this method, data and the related aggregations are saved in RDBMS, and OLAP middleware is used to execute the handling and exploration of data cubes.

This architecture targets the optimization of the RDBMS back end and supports more tools and services including data cube navigation logic. Because of the use of the RDBMS back end, the main benefit of ROLAP is scalability in managing high data volumes.

These are the intermediate servers that stand in among a relational back-end server and client front-end tools. They need a relational or extended-relational DBMS to save and manage warehouse data, and OLAP middleware to provide the missing item.

ROLAP servers involve optimization for each DBMS back end, execution of aggregation navigation logic, and more tools and services. ROLAP technology influence to have higher scalability than MOLAP technology. The DSS server of Micro strategy, for instance, adopts the ROLAP method.

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

Relational OLAP is the recent and fastest growing OLAP technology segment in the industry. Some vendors have entered the fray in this direction (e.g. Sagent Technology and Microstrategy).

This approach enables multiple multidimensional views of two-dimensional relational tables to be created, avoiding structuring data around the desired view. There are few products in this section have supported strong SQL engines to support the difficulty of multidimensional analysis.

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. Although 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.

This contains creating multiple SQL statements to manage user requests and also being capable of making the SQL statements depending on the optimizer of the DBMS engine. While flexibility is the new feature of ROLAP, there exist products that needed the use of denormalized database design.