Working with Data Sources and Data Source Views - Professional SQL Server Analysis Services 2005 with MDX - page 145

Figure 4-8
Specifying Primary Keys and Relationships in the DSV
It is likely that you will encounter underlying databases without the primary
key to foreign key relationships that you will need in place for preparation of
data for analysis; that is, building dimensions and cubes. The DSV wizard ex-
tracts primary keys and the relationships specified in the underlying relational
database to form primary keys and the relationships represented in the DSV.
As mentioned, perhaps some of the OLTP systems you use do not have the
primary keys and relationships specified in the relevant tables — or when you
design your data warehouse you might want to change these to suit your data
warehouse design. The DSV designer provides you with the functionality to
specify primary keys for the tables that do not have them already, and in this
way you can effectively modify or add new relationships between the tables in
the DSV.
To specify the primary key(s) for a table, you need to do the following in the
DSV Designer:
1. Select the column in the table that you want to specify as a primary
key. If there is more than one column that forms the primary key, you
can do multiple selections by holding the Ctrl key. If the tables have
auto-increment setup for the key column in the database then you
will not be able to change the primary key(s) of the tables.