Every project can be optionally classified into different categories. Within these categories, a project can be further categorized into different classification codes. Depending on how these classification categories are defined in the application, for some categories, a project can be classified with more than one classification code.
The Project Classification Table (W_PROJ_CLASSIFICATION_D) is at the grain of Project, Classification Category and Classification Code. The Project facts do not have an explicit foreign key for joining with Project Classification Dimension; instead the join is on the Project Foreign Key. As specifying a Classification Category is optional for a project, so the logical join in the BI metadata repository (that is, the RPD file) between the Facts and Project Classification Dimension has been set as right outer join to avoid losing records in case the project has not been classified.
A particular classification code might exist for more than one classification category. Therefore, to avoid double counting, it is important that a classification category is fixed in a report that has classification code as one of the reporting attributes. If a Project belongs to more than one Classification Category under the same Classification, the Project metrics (Cost, Revenue, and so forth) will be double counted.