SQL Server Reporting Services 2012 Projects with Visual Studio 2012 - Learning SQL Server Reporting Services 2012 - page 100

19. The Tablix Properties window, as shown in the previous screenshot,
will appear with the default Filters section now empty.
20. The Filters section is provided so that you can apply an equivalent of
"where" clause to the dataset. The Expression drop-down window lists
the columns on which you may impose the "where" clause. The Operator
drop-down list provides the various arithmetic/logic constraints that
you can use, and the Value box is where you type a value, as described
in the next two steps.
21. Click on Add in the Change Filters area and click on OK .
The Change Filters window changes, as shown in the following screenshot:
22. Use the handle for Expression and choose [OrderQty] , as follows: