Implicit Fact Column in OBIEE

In case we have multiple Fact tables, then it is a best practice to set an Implicit Fact Column. BI Server to make the best choice between two possible query paths.You need to select a fact attribute (measure) as an implicit fact column.

Whenever User request a report with only Dimensions and there is no Fact columns. Then BI server identified there is multiple query paths. The BI Sever will fetch the reports from the nearest fact table, these result may be different form expected result.

So, In  order to avoid this kind of error, we can create a dummy fact column called Implicit Fact Column in physical layer.You can find this functionality in the general property of a subject area in the repository. Join all dimensions to this fact column in BMM Layer.In presentation layer, double click the presentation catalog or go to properties of presentation catalog.In the general tab, find the Implicit Fact Column section. So, whenever a report on Dimensions is requested it joins through dummy fact table and fetches data.

Steps to set Implicit Column

1.  Select properties of presentation catalog in presentation layer.

2.  In implicit fact column section click on set and select any measure column from fact table.

3.  Click OK and save

Setting the Dummy Columns as Implicit Face Column

1.  Create a Physical Column in Fact table in Physical Layer.

2.  Name it as Implicit_Column.

3.  Drag this column in Fact table from BMM layer.

4.  Double click on logical table source of fact table.

5.  In content tab, assign any numeric value to Implicit_Column.

Once this is done we can set this column as Implicit Fact Column in Presentation catlog as mentioned above.