We encountered an interesting issue when adding an alternate period hierarchy in EPM Cloud Planning. Generally speaking, adding alternate hierarchies to a dimension is straightforward. We had previously added alternate hierarchies without any issues.
We needed a hierarchy for specific periods representing summer, only May thru Sep. The new hierarchy was created after H2 with the shared members.
But on refresh we got an error.
Thanks to Google, we came across information about restrictions on alternate hierarchies in the period dimension. It was challenging to interpret, but basically the members need to be balanced and in sequence. This means that all 12 base period members have to be represented in the alternate so they have an equal number of shares across the dimension. We needed 5 members for the summer, but we had to add the other 7 as well to keep it balanced.
Creating additional hierarchies to include the other periods resolved the issue. The hierarchy Summer has the periods needed, but adding Pre Summer and Post Summer allowed us to include the remaining members and achieve the balance that Planning requires. And we needed Pre and Post so as to keep the members in sequence. Putting all the non-summer members in one hierarchy did not work.
As always, happy EPM’ng!