Databases Reference
In-Depth Information
The
Flights
table is the fact table, containing all of the measures as well as links to
the surrounding dimension tables. A big advantage of the star schema is that it can
be easily understood, and business users can easily recognize the names of the tables
and how they relate to each other.
The snowflake schema
In the earlier example, each dimension table is completely denormalized. There is
a second type of dimensional model in which dimensions are not necessarily fully
flattened. This is called a snowflake schema as (again with some imagination) the
diagram resembles a snowflake. An example is depicted in the following screenshot.
It is basically the same schema as the previous example, but the
Aircraft
dimension
is not completely denormalized.
