Insufficient Permissions When Adding Field

[MKF62]

I am a newbie to this whole database user/role management thing. I have a dbo-owned database where I created an "Editor" role. I assigned this role to a new user I created. I then changed the privileges on one feature class to allow any user in the Editor role to select, insert, update, and delete. 

I then run my python script using a connection file derived from the new user's credentials. In the script, I attempt to add a field to the feature class mentioned above. I received an error message saying I have insufficient permissions, but I am unsure why. I have a hunch it is because this user is not the owner of the data, but if it has editing permissions I figured it would be able to add a field despite not being the owner. I am able to edit successfully with this user, but I cannot add fields.

There are no locks on the database. The database is not versioned. I am working in 10.5.

[Asrujit_SenGupta · Accepted solution]

Yes, you can only make schema changes, when connected as the Data Owner.

There are some tasks-- schema changes, grant privileges, Register as Versioned, etc which only the Data Owner can perform.

[MKF62]

So in theory, I could add the field ahead of time and then just calculate that field in the script with my new user since my user can edit but can't "create"?

[Asrujit_SenGupta]

Yes, that will work fine. Or use the Dataowner user to add\delete\update fields, as and when needed.