Lists in Anaplan have two main settings related to how data is aggregated:
- Top level item.
- Parent hierarchy.
They may both be set on the “Configure” tab of the List settings screen.
Top Level Item
这个列表已经有一个top level item, “All Regions”.
当在模块中使用时，顶级项目包含整个列表中订单项数据的聚合。下面是一个简单的模块，说明了这一点：
拥有顶级项目的一个优点是，它可以用于为其他模块中没有列表作为尺寸的订单项提供摘要值。下面的模块没有任何尺寸，因此显示的公式将使用顶级项目提供单元格值。如果列表没有最高级别的项目，这将是不可能的。
Not all lists require a top level item. For example, a simple pick list of currencies would not require a top level item as it is not necessary to aggregate data over the list.
As a rule of thumb, if a list will not be used as a dimension of a module, then it will not need a top level item.
Top level items can also have implications for performance. The summary will be calculated every time an item is added to the list. For large flat lists, such as transaction lists, this can add significantly to the amount of calculations that the model will have to do. This means that it is probably a good idea not to set a top level item on this kind of list, even if it is used as a module dimension.
父层次结构
This list has been given a parent hierarchy. One point to note is that it is possible to set a top level item and a parent hierarchy on the same list. In this case, the setting of the top level item is ignored in favor of the parent hierarchy setting.
A simple module using this list is shown below.
It can be seen that the detail cells in blue are summed up into their relevant parent item, in black. These are, in turn, aggregated into the total for the “All Regions” top level item. These values can be used in a similar way to the top level item for providing summary items for modules that do not have the list as a dimension.
In the case where the parent hierarchy, in this case Regions, is a dimension of the line item, then the summary values are used to provide the cell values.
In the case where the parent hierarchy is not a dimension of the line item, then the top level item of the parent hierarchy is used to provide the summary value:
More Information
For more information on this subject, and other foundational subjects, visit the Level 1 Model Building course in theAnaplan Academy.
