What is HOLAP?

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HOLAP represents Hybrid OLAP. It can manage a tradeoff between ROLAP’s scalability and MOLAP’s query implementation, some commercial OLAP servers are depended on the HOLAP method. In this case, the user determines which portion of the data to save in the MOLAP and which in the ROLAP. For example, generally, the low-level data are saved using a relational database, while higher-level data, including aggregations, are stored in an independent MOLAP.

HOLAP is a mixture of ROLAP (relational OLAP) and MOLAP (multidimensional OLAP) which are different implementations of OLAP. HOLAP enables storing elements of the data in a MOLAP store and another element of the data in a ROLAP store, enabling a tradeoff of the benefits of each. The degree of control that the cube designer has over this separation change from product to product.

Because hybrid OLAPs allows the use of several set of the two OLAPs, they generally save data in both a relational database and a multidimensional database. As a result, the decision to access one of the two databases is based on which is best suited for the desired processing type or software.

This supports much more flexibility when managing data. For huge data processing, the data is saved in a relational database, while for theoretical processing, the data is saved in a multidimensional database. This method is useful in the following situations which are as follows −

  • If there are volumes of information that cannot be managed by one multidimensional database.

  • If there are instances of performance bottlenecks whenever information is being accessed from a server.

  • If there is a requirement to use existing summarized and organized data sources.

Types of HOLAP

There are various types of HOLAP which are as follows −

Web-Enabled OLAP (WOLAP) Server − WOLAP applies to OLAP application which is accessible via the web browser. Unlike traditional client/server OLAP applications, WOLAP is treated to have a three-tiered architecture which includes three components are a client, a middleware, and a database server.

Desktop OLAP (DOLAP) Server − DOLAP allows a user to download an area of the data from the database or source, and work with that dataset locally, or on their desktop.

Mobile OLAP (MOLAP) Server − Mobile OLAP allows users to access and work on OLAP data and software remotely through the use of their mobile devices.

Spatial OLAP (SOLAP) Server − SOLAP contains the capabilities of both Geographic Information Systems (GIS) and OLAP into a single user interface. It supports the administration of both spatial and non-spatial data.

Published on 23-Nov-2021 10:29:00