Explicit Hierarchies (Master Data Services)
An explicit hierarchy uses consolidated members that you create explicitly for the purpose of grouping other members. All members in an explicit hierarchy come from a single entity.
In this example, Subcategory leaf members are grouped by Subcategory consolidated members.
.gif "Explicit hierarchy")
An explicit hierarchy includes all of the leaf members from the entity. Consolidated members belong to one explicit hierarchy at a time. If multiple explicit hierarchies exist, consolidated members can belong to only one of the hierarchies.
An explicit hierarchy is different than a derived hierarchy because a derived hierarchy contains multiple entities, does not contain consolidated members, and contains a consistent number of levels.
An explicit hierarchy can be ragged, which means that the hierarchy can end at different levels simultaneously. Each consolidated member can have an unlimited number of consolidated and leaf members underneath, or can have none. The leaf members can be under a single consolidated member or under multiple levels of consolidated members.
Before you can create an explicit hierarchy, the entity must be enabled for explicit hierarchies.
Example
In the following example, the Product entity contains these leaf members: BK-M101 {Mountain-100}, BK-M201 {Mountain-200}, BK-M301 {Mountain-300}, BK-R150 {Road-150}, BK-R450 {Road-450}, and BK-R650 {Road-650}.
To summarize these leaf members at specific consolidation points, you can create consolidated members in the Product entity. Insert the consolidated members at levels in the hierarchy tree where you want to summarize the leaf members. There is no limitation on where you insert your consolidated members; however, each member (leaf or consolidated) can be used only once.
.gif "Explicit hierarchy example")
Consolidated members can be used to group members at any level, and leaf and consolidated members are sorted in the order you determine.
Types of Explicit Hierarchies
There are two types of explicit hierarchies: mandatory and non-mandatory.
Mandatory Explicit Hierarchy
A mandatory explicit hierarchy is a hierarchy in which all leaf members must be included in the hierarchy tree. By default, all members are included at the root of the tree. You can rearrange the members as needed.
Non-Mandatory Explicit Hierarchy
A non-mandatory explicit hierarchy is a hierarchy in which all leaf members are in a system-created Unused node. You can move members out of this node as you need them. The rest of the members can remain in the Unused node.
When you use non-mandatory explicit hierarchies, any reporting or analysis done on the hierarchy may not match reporting or analysis done on mandatory hierarchies.
Rules
The following rules apply to explicit hierarchies (both mandatory and non-mandatory).
Each leaf member can be included in the hierarchy only once.
All consolidated members must be included in a hierarchy.
Consolidated members cannot be in more than one explicit hierarchy.
Consolidated members in the hierarchy tree do not have to contain leaf members underneath them.
If you delete an explicit hierarchy, all consolidated members that were used in the hierarchy are deleted.
If you delete a consolidated member that was in an explicit hierarchy, all leaf members that were grouped by that consolidated member are moved to the root.