Question

Explain the difference in processing between a star-schema and an OLAP Cube. What are the benefits and drawbacks of each type?

Answer 1

Star Schemas are dimensional structures deployed in a RDBMS (Relational Database Management System) . They characteristically consist of fact tables linked to associated dimension tables with primary/foreign key relationships.

OLAP is defined as a dimensional structure implemented in a multidimensional database; it can be equivalent in content to, or more often derived from, a relational star schema. An OLAP cube contains dimensional attributes and facts, but it is accessed through languages with more analytic capabilities than SQL, such as XMLA.

Advantages ~

*Star Schema

• It offers better Query performance because a star schema database has a small number of tables and clear join paths.
• Offers greater Load performance and administration- Structural simplicity also reduces the time required to load large batches of data into a star schema database.
• Offers Built-in referential integrity- star schema has referential integrity built in when data is loaded. Referential integrity is enforced because each record in a dimension table has a unique primary key, and all keys in the fact tables are legitimate foreign keys drawn from the dimension tables.
• It is Easy to understand - star schema is easy to understand and navigate, with dimensions joined only through the fact table.

.*OLAP Cube

• It can Share Intelligent Cube data securely

  MicroStrategy’s centralized metadata and Intelligence Server architecture allows Intelligent Cube to be shared securely.

• It can Schedule Intelligent Cube execution and maintenance

  To reduce stress on the Intelligence Server, you can schedule when Intelligent Cubes are executed which basically allows you to take advantage of Intelligence Server down time to run Intelligent Cubes without affecting performance for your user community.

• It canApply security restrictions on users and objects..Gcc