Cognos Dynamic Cubes is meant to provide high-performance interactive analysis of data. It is used when your data volume is over terabytes. They are used only for star or snowflake modeled data warehouses and provides in-memory relational OLAP functionality with aggregation.
When to Use Cognos Dynamic Cubes
Cognos Dynamic Cubes was developed to address the challenge of high-performance and low latency interactive analysis and reporting against terabytes of data. DMR (Dimensionally Modeled Relational) and OOR (OLAP Over Relational) are meant for low to medium volume of data. When used for data sources with high data volume, it results in poor performance. So when we require high performance and low latency, high volume data analysis and reporting, we have to use Cognos Dynamic Cubes.
Comparison of Dynamic Cubes to Other Cognos OLAP Technologies
Cognos provides various data solutions for different requirements of data. Each one is meant for handling various data problems.
Cognos TM1 is a MOLAP Technology that can handle medium data volumes. Aggregation takes place on the fly, which degrades the performance with very large volumes of data and users.
IBM Cognos PowerCubes is a MOLAP Technology that uses pre-aggregation of data. Cube does not have any active connection to the data source, so they are said to be static. It is used for interactive analysis of operational or transactional data. It causes data latency when movement of data happens.
DMR is an OOR Technology and it is used when we need a dimensional advantage in relational data. It can be used for the analysis of a low volume of data.
Dynamic Cubes are used for the analysis of large volumes of data. It supports in-memory caching through DQM. It can be used only for star or snowflake data sources. It minimize the data movement between relational sources and dynamic cube engines. All dimensions are preloaded here.
Requirements to use Dynamic Cubes :
- It requires sufficient server RAM.
- It requires 64 bit Report Server enabled.
- It is available in Cognos 10.2 or higher versions.
- It supports DB2, Netezza, Microsoft SQL Server, Oracle, Teradata databases.
- It requires IBM Cognos Cube Designer.
Steps for Implementing Dynamic Cubes:
- Create the data source connection to import metadata from the relational database.
- Find out measures, dimensions, keys, captions, levels, and the defining relationships between them, the creation of required calculated members, defining pre-defined aggregation.
- Define security for dimensions, measures.
- Publish Dynamic Cube into Cognos BI environment.
- Leverage IBM Cognos Administration to assign Dynamic Cube to the Query Service.
- Dynamic Cube needs to be started before it can be leveraged.
- To quickly deploy dynamic cubes, we have options available in Cube Designer