After a quick test (because I don't know the answer) The only difference I can see is with the [Authentication_Type] and [Authentication_type_desc] in sys.database_principals.name authentication_type authentication_type_desc---------------------------------------- ----------------------------testLogin 1 INSTANCEtestUserNoLogin 0 NONE
My test code:use junkgocreate login testLogin with password = 'testLogin', check_policy = offcreate user testLogin for login testLogincreate user testUserNoLogin without loginselect name, authentication_type, authentication_type_desc from sys.database_principals where name like 'test%'godrop user testUserNoLogindrop user testLogindrop login testLogingo
Be One with the OptimizerTG