Error: Failed to compress the database: The column cannot be modified because it is either a computed column or is the result of a UNION operator
When trying to compress a SQL Server database, the following error may be returned:
"Failed to compress the database:
Underlying DBMS error [[Microsoft][SQL Server Native Client 11.0][SQL Server]The column cannot be modified because it is either a computed column or is the result of a UNION operator.]"
SQL Server database tables that contain computed columns cannot be compressed because the geodatabase does not support auto-populated fields such as computed columns or auto-incrementing fields.
Solution or Workaround
Data tables with computed columns can be viewed in ArcGIS using Database Views or Query Layers, but the use of these tables for editing is not supported.
ArcGIS 10.3 Web Help: Create Database View
ArcGIS 10.3 Web Help: Creating a query layer
Removing the computed column allows edits to be compressed successfully.