The first step in converting from an ER schema to a dimensional schema is dividing the ER schema into separate business processes. Each of these business processes will be modeled into a separate star schema.

The next step is to declare the granularity of the business process (for example, a single flight or one salary payment). We then group the measures that are used in the business process into a single fact table.

After that, the remaining tables are flattened into dimension tables and directly linked to the fact table using a single key. It is possible for the same dimension table to be used in multiple star schemas. This is called conformed dimension. For example, the employee dimension can be used in the context of Airline Operations as well as in the payroll context.