Siebel Analytics Server Administration Guide > Working in a Repository's Business Model and Mapping Layer > Business Model and Mapping Layer Objects >

Working with Logical Columns

Logical columns are displayed in a tree structure expanded out from the logical table to which they belong. If the column is a primary key column or participates in a primary key, the column is displayed with the key icon. If the column has an aggregation rule, it is displayed with a sigma icon. Logical columns in the Business Model and Mapping layer, as well as presentation columns in the Presentation layer, may be reordered.

This section includes the following topics:

Creating or Editing a Logical Column

Use the General tab to create or edit the general properties of a logical column. You can create a logical column object in the Business Model and Mapping layer, and then drag and drop it to the Presentation layer.

To create or edit a logical column

  1. Access the Logical Column dialog box by right-clicking a logical table in the Business Model and Mapping layer, and then selecting New Object > Logical Column from the shortcut menu.
  2. Select the General tab.
  3. Specify a name for the logical column.

    4. The name of the column and its associated path appear in the Belongs to Table field.

  4. If you want the logical column to be derived from other logical columns:
  5. (Optional) Enter a description of the logical column.

    6. NOTE:  The type and length fields are populated automatically based upon the column's source.

Using the Logical Column Dialog Box—Datatype Tab

Use the Datatype tab to view information about the logical column. You can also edit the logical table sources from which the column derives its data, or unmap it from its sources.

To edit the logical table source

  1. Select the logical table source you want to edit and double-click it.

    2. The Logical Table Source dialog box appears.

  2. Make your changes, and click OK to return to the Logical Column dialog box.

To unmap a logical column from its source

Setting Default Levels of Aggregation for Measure Columns

Use the Aggregation tab of the Logical Column dialog box to set default levels of aggregation for measure columns.

You need to specify aggregation rules for logical columns that are measures (and which are not already mapped to existing logical columns).

TIP:  When you specify a default aggregation, that aggregation is always performed on requests for the column. To prevent confusion, you may want to incorporate the aggregation method into the column name. For example, if the column measures sales dollars and the default aggregation is SUM, name the column something like SumOfDollars.

To specify a default aggregation rule for a measure column

  1. In the Aggregation tab of the Logical Column dialog box, select one of the aggregate functions from the Default Aggregation Rule drop-down list.

    2. The function you select is always applied when an end user or an application selects the column in a query.

  2. Click OK.

Setting Up Dimension-Specific Aggregate Rules

Use the Aggregation tab of the Logical Column dialog box to set up dimension-specific aggregate rules.

The majority of measures have the same aggregation rule for each dimension. Some measures, however, can have different aggregation rules for different dimensions. For example, bank balances might be averaged over time but summed over the individual accounts. The Siebel Analytics Server allows you to configure dimension-specific aggregation rules; that is, to specify one aggregation rule that applies to a given dimension and other rules that apply to other dimensions.

You need to have dimensions configured in the Business Model and Mapping layer in order to set up dimension-specific aggregation.

For more information about setting up aggregate navigation, see Setting Up Aggregate Navigation.

To specify dimension-specific aggregation rules for a column

  1. In the Aggregation tab of the Logical Column dialog box, select the option Use advanced options.

    2. The Advanced options section of the dialog box becomes active.

  2. Click New to open the Browse window, where you can select a dimension over which you want to perform aggregation.
  3. Select a dimension over which you want to perform aggregation and click OK.

    4. The dimension is added to the list.

  4. Click the Expression Builder button to the right of the Features column to open the Expression Builder for Aggregates.
  5. You can enter the aggregation to perform over the dimension directly into the Formula area, such as SUM(SalesFacts.PlanRevenue), or you can use the Expression Builder to configure the aggregation.

    6. For example, if you have a time dimension and you want the calculation to determine the average over time and the sum over the other dimensions, the expression you create in the Expression Builder would be:

    AVG(<column_name>)

    where column_name is the name of the logical column.

  6. If you have other dimensions for which you want to set up dimension-specific aggregation rules, repeat Steps 2 through 5.
  7. Specify the aggregation rules to use for all the other dimensions in the entry labeled Other.
  8. Use the Up and Down buttons to specify the order in which the dimension-specific rules are performed. When calculating the measure, the aggregation rules are applied in the order (top to bottom) configured in the dialog box.
  9. Click OK to save your modifications.

    10. NOTE:  If you use dimension-specific aggregation rules, make sure the users understand the definition of the column. In the example shown in Step 5, the user is not able to determine the sum over time. You would have to create another column to answer that question.

To reorder an aggregation rule

  1. In the dimension or formula, select the rule you want to reorder.
  2. Use the drag-and-drop feature to reposition the rule, or click the Up and Down buttons.

Using the Logical Column Dialog Box—Levels Tab

Attributes can be associated with a level by selecting the dimensional level on this tab. Use the Levels tab to associate a level-based measure (or any attribute) with multiple dimensions to address your organization's analytical requirements. This allows you to analyze, for example, regional share of product sales by both category and country.

Dimensions are displayed in the Dimensions list. If this attribute is associated with a level, the level is displayed in the Levels list.

The fastest way to associate a measure with a level in a dimension is to expand the dimension tree in the Business Model and Mapping layer, and then use the drag-and-drop feature to drop the column on the target level. You can also make the associations from the Levels tab. For more information about level-based measures, see Level-Based Measure Calculations.

To associate this measure with a level in a dimension

  1. Click in the white space in the Levels list next to the dimension you want to select a level from.

    2. A drop-down list appears.

  2. Select the level.
  3. Repeat this process to associate this measure with other levels in other dimensions.

To remove an association

  1. Click the Delete button next to the level association you want to remove.

    2. The level is removed from the Levels list.

  2. Repeat this process to remove associations with levels in other dimensions.

 Siebel Analytics Server Administration Guide 
 Published: 23 June 2003