SSAS - Designing approaches for dimensional model

In SSAS, there are two ways to design dimensional models. Top-down or bottom up.

Top Down Approach

• This is generally not much used option.
• The relational data source does not exist in this case. The tables are created from the dimensional model from SSAS.
• Cube and dimension wizards has the option to implement this option.
• Schema Generation Wizard is used to generate and deploy schema in the database..
• DBO permission required in order to create database objects.

Bottom Up Approach

• Most of the times this is the approach thats taken.
• The data mart already exists.
• The dimensional model and cubes are designed from the Relational tables in the Data Mart.
• Cube and Dimension wizards have the option to implement this solution.