A Dimension view is a database view of a Dimension table. It may be a full or partial view. It is typically used in cases such as date dimensions, where multiple date dimensions exist for one Fact table. In many data warehouses Dimension views are built as part of the end-user layer but creating them in the data warehouse means they are available regardless of the end-user tools used.
Views are displayed in WhereScape RED either as part of the Dimension object group or in a separate object group—Dimension View. The default is to view Dimensions and Dimension Views together:
This visualization option is set from the Tools > User Preferences > Look and Feel menu item:
This example shows Dimensions and Dimension Views as separate object types:
Creating a Dimension View
- Double-click Dimension (or Dimension View) in the left pane.
- Browse the data warehouse in the right pane.
- Drag a table from the right pane into the middle pane.
- The Add New Metadata Object window defaults the object type to a Dimension view
- Change the view name as required and then click Add.
- The View Column Definition window appears to provide a means of re-mapping some of the column names in the view if required.
- Click OK, the View properties window is displayed:
- Select the Distinct Data Select check box if you want the view to return only different values.
- A 'Where' clause could be entered, but this can be done later. Normally you would just click OK.
- A prompt appears to indicate that the view has been defined.
- Because this is a Dimension view, you are given the option to create both the view and an associated Get Key function. For any other view type, a Get Key function is not created.
- If you click Create View + Function, the following window appears which enables you to select a business (natural) key for the Dimension view.
