HOLAP is a combination of ROLAP

ROLAP

ROLAP stands for Relational Online Analytical Processing.ROLAP is an alternative to the MOLAP technology...

 (Relational OLAP) and MOLAP

MOLAP

MOLAP stands for Multidimensional Online Analytical Processing.MOLAP is an alternative to the ROLAP technology...

 (Multidimensional OLAP) which are other possible implementations of OLAP

OLAP

In computing, online analytical processing, or OLAP , is an approach to swiftly answer multi-dimensional analytical queries. OLAP is part of the broader category of business intelligence, which also encompasses relational reporting and data mining...

. HOLAP allows storing part of the data in a MOLAP

MOLAP

MOLAP stands for Multidimensional Online Analytical Processing.MOLAP is an alternative to the ROLAP technology...

 store and another part of the data in a ROLAP

ROLAP

ROLAP stands for Relational Online Analytical Processing.ROLAP is an alternative to the MOLAP technology...

 store, allowing a tradeoff of the advantages of each. The degree of control that the cube designer has over this partitioning varies from product to product.

Vertical partitioning

In this mode HOLAP stores aggregations in MOLAP

MOLAP

MOLAP stands for Multidimensional Online Analytical Processing.MOLAP is an alternative to the ROLAP technology...

 for fast query performance, and detailed data in ROLAP

ROLAP

ROLAP stands for Relational Online Analytical Processing.ROLAP is an alternative to the MOLAP technology...

 to optimize time of cube processing.

Horizontal partitioning

In this mode HOLAP stores some slice of data, usually the more recent one (i.e. sliced by Time dimension) in MOLAP

MOLAP

MOLAP stands for Multidimensional Online Analytical Processing.MOLAP is an alternative to the ROLAP technology...

 for fast query performance, and older data in ROLAP

ROLAP

ROLAP stands for Relational Online Analytical Processing.ROLAP is an alternative to the MOLAP technology...

. Moreover, we can store some dices in MOLAP

MOLAP

MOLAP stands for Multidimensional Online Analytical Processing.MOLAP is an alternative to the ROLAP technology...

 and others in ROLAP

ROLAP

ROLAP stands for Relational Online Analytical Processing.ROLAP is an alternative to the MOLAP technology...

, leveraging the fact that in a large cuboid, there will be dense and sparse subregions.

Products

Examples of commercial products which support HOLAP storage mode are Microsoft Analysis Services

Microsoft Analysis Services

Microsoft SQL Server Analysis Services is part of Microsoft SQL Server, a database management system. Microsoft has included a number of services in SQL Server related to business intelligence and data warehousing. These services include Integration Services and Analysis Services...

, Oracle Database OLAP Option

Oracle OLAP

The Oracle Database OLAP Option implements On-line Analytical Processing within an Oracle database environment. Oracle Corporation markets the Oracle Database OLAP Option as an extra-cost option to supplement the "Enterprise Edition" of its database...

, MicroStrategy

MicroStrategy

MicroStrategy, Inc. , is a business intelligence software vendor. MicroStrategy's software enables leading organizations worldwide to analyze the vast amounts of data stored across their enterprises to make more strategic business decisions...

 and SAP AG

SAP AG

SAP AG is a German software corporation that makes enterprise software to manage business operations and customer relations. Headquartered in Walldorf, Baden-Württemberg, with regional offices around the world, SAP is the market leader in enterprise application software...

BI Accelerator.The hybrid OLAP approach combines ROLAP and MOLAP technology,
benefiting from the greater scalability of ROLAP and the faster computation of MOLAP. For example, a
HOLAP server may allow large volumes of detail data to be stored in a relational database, while aggregations
are kept in a separate MOLAP store. The Microsoft SQL Server 7.0 OLAP Services supports a hybrid OLAP
server