A business cube is based on tables (including views). By default, there is no relationship between the tables. In order to make them correlated, you need to define joins among them. To do this, in the Business Cube Editor window, click Tools > Join Editor and the Business Cube - Join Editor window will then be displayed with which you can set up joins easily as required.
Note: Because a report cube is based on a query, stored procedure, SQL file, or user defined data source, which may already contain some relationship among tables, you cannot set joins for it.
See also Business Cube - Join Editor window for detailed explanation about options in the window.
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