Symptoms
Assume that you have an entity that contains collections and explicit hierarchies in SQL Server 2016 Master Data Services. If you delete all the explicit hierarchies of the entity, you cannot add new explicit hierarchies to the entity. Additionally, you receive an error message that resembles the following:
Errors
2705 : Column names in each table must be unique. Column name 'Child_HP_ID' in table 'mdm.tbl_12_50_CM' is specified more than once., @ErrorNumber = 2705, @ErrorProcedure = "", line 3, @ErrorNumber = 50000, @ErrorProcedure = "udpEntityHierarchySave"
Resolution
The fix for this issue is included in the following cumulative update for SQL Server:
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
References
Learn about the terminology Microsoft uses to describe software updates.