Creating subsets

Subsets are a limited set of items from a dimension.

Some examples of how you can use subsets are described below:

  • Create a subset for use with a pick list in a calculation dimension to limit the number of items in the pick list.
  • Create a subset from a time dimension to limit the number of months a user sees in a view.
  • Create a subset to hide a total from a list of products.

A subset is a selection from the parent dimension. Subsets can be static or dynamic. If dynamic subsets from other IBM® Cognos® TM1® interfaces, such as Cognos TM1 Architect and Cognos TM1 Perspectives are opened with IBM Cognos TM1 Performance Modeler, the MDX expression is shown in the properties and the user is warned. If you edit a dynamic subset, the subset is saved as a static subset.

You can use filters in subsets. For example, if you have a postcode attribute, you could search for all properties with a postcode that begins with SW. You can use filters to add and remove members from an existing subset.

Procedure

  1. Right-click the dimension name in the Model Design pane and click New > Subset
  2. Type the name for the subset and click OK.
  3. Select the members that you want to include in the subset.
    There are different methods of doing this:
    • Hide the members that you do not want in the subset, or
    • Use the filter filter to select which elements that you want in the subset. For more information, see Using a filter in a subset.
    To hide the members:
    1. Right-click a representative member for the level that you want to apply to the subset.
      For example, if you have Year, Months, Weeks as time periods, and you want to use months only, right-click any month member.
    2. Select the appropriate Hide command from the selection box.
    Note: When you hide a member in a subset, the member is not deleted.
  4. Choose how the members in the subset appear.
    For example, you can do the following operations:
    • Sort the members in a subset by right-clicking on a member and choosing one of the sort options.
    • Expand all or collapse all members in a dimension.
    • Move members up and down.
  5. Save the subset.

Example

Take a dimension that is named Country and region and create a subset that is named Europe.

The Country and region dimension contains the following members:

  • All Subsidiaries
    • Americas
    • Asia Pacific
    • Europe
      • Central Europe
      • Northern Europe
      • Southern Europe

To create the Europe subset, perform the following steps:

  1. Right-click the dimension that is named Country and region and select New > Subset. Name the subset Europe.
  2. Right-click the Europe member and select Hide others.
  3. Expand the Europe member so that the leaf members are displayed and save the subset.

The Europe subset contains the following items:

  • Europe
    • Central Europe
    • Northern Europe
    • Southern Europe