In a hierarchy with a time-dependant structure, nodes/leaves can be defined more than once but each node/leaf needs to have its own time-validity. The hierarchy itself is not time-dependent.
The following example shows that node "03" (= "LOCATION 3") is a child of 3 text-nodes (NODE1, NODE2 and NODE3) depending on which keydate is used for hierarchy "JP_HIER_TD":
With keydate 31.05.2007, node "3" is a (postable) node hanging under text-node "NODE2":
With keydate 14.05.2018, node "3" is a leaf hanging under text-node "NODE3":
- Table RSRHIEDIR_OLAP (please see BW Hierarchy Tables for more details on this table) which is used by OLAP to identify a hierarchy only uses one HIESID-value for a hierarchy with a time-dependant structure. However, it uses several SVER-values for each keydate(where the hierarchy changes) in field HDATE. Each keydate/SVER-entry represents a different hierarchy-structure of the same hierarchy.
The hierarchy-structure of hierarchy "JP_HIER_TD" valid for 31.05.2007 has the HIESID 13.772 and SVER-value A.
The hierarchy-structure valid for 14.05.2018 has the same HIESID 13.772, but a different SVER-value 9.
- Every HIESID-SVER-combination in table RSRHIEDIR_OLAP has a full hierarchy structure materialized in the I-table (in our example table "/BIC/IFABC_ORT").
- If a hierarchy is used in the reporting for which no SVER-value yet exists in table RSRHIEDIR_OLAP, a new SVER-entry is created and a full materialization of that particular hierarchy-structure for this keydate is generated.
- In the worst-case scenario, a time dependent hierarchy structure is different for each day. However in most cases there will be time-intervals in which the hierarchy structure does NOT change at all. These time intervals in which the hierarchy structure does not change are maintained in table RSRHIEDIR_TIMDEP.
f.e. if a query uses keydate 01.08.2012 for hierarchy "JP_HIER_TD", it will display the same hierarchy-structure as shown above for keydate 14.05.2018. OLAP will retrieve HIESID 13.772 and SVER 9 from table RSRHIEDIR_OLAP.