Lesson 4: Mark as Date Table
Applies To: SQL Server 2016
In Lesson 2: Add Data, you imported a dimension table named DimDate. You then renamed the DimDate table, in Lesson 3: Rename Columns, to simply, Date. While in your model this table is now named Date, it can also be known as a Date table, in that it contains date and time data.
Whenever you use Time Intelligence functions in calculations, as you will do when you create measures a little later, you must specify date table properties, which include a Date table and a unique identifier Date column in that table. You can then create valid relationships between other tables and the Date table; necessary for calculations using DAX time intelligence functions.
In this lesson, you will mark the imported and renamed Date table as the Date table and the Date column (in the Date table) as the Date column (unique identifier). All the use of the name Date can get kind of confusing, but you’ll soon get the idea.
Estimated time to complete this lesson: 3 minutes
This topic is part of a tabular modeling tutorial, which should be completed in order. Before performing the tasks in this lesson, you should have completed the previous lesson: Lesson 3: Rename Columns.
In the model designer, click the Date table (tab).
Select the Date column, and then in the Properties window, under Data Type, make sure Date is selected.
Click the Table menu, then click Date, and then click Mark as Date Table.
In the Mark as Date Table dialog box, in the Date listbox, select the Date column as the unique identifier.
To continue this tutorial, go to the next lesson: Lesson 5: Create Relationships.