Solutions to the Exercises

2.1

$CB_HOME/bin/CBserver -p 5544 -d TutApp

2.2

Select "Connect CB Server" from the Server menu. An interaction window appears, querying the host name and the port number of the server you want to connect to. Enter the name of the host the server was started on and the portnumber specified by the -p parameter, then select "Connect".

3.1

Department in Class
end

3.2

To load an object from the object base into the editor-window, select the frame button or Load frame from the Edit menu.

3.3

Department in Class with
     attribute
            head: Manager
end

3.4

Lloyd in Manager                     Eleonore in Manager
end                                  end
Phil in Manager                      Albert in Manager
end                                  end

Production in Department with        Administration in Department with
  head                                 head
    head_of_Production : Lloyd           head_of_Administration : Eleonore
end                                  end

Marketing in Department with         Research in Department with
  head                                head
    head_of_Marketing : Phil             head_of_Research : Albert
end                                  end

Lloyd in Manager with                Phil in Manager with
  salary                                salary
      LloydsSalary : 100000                 PhilsSalary : 120000
end                                  end

Eleonore in Manager with             Albert in Manager with
  salary                               salary
    EleonoresSalary : 20000              AlbertsSalary : 110000
end                                  end

3.5

Michael in Employee with             Maria in Employee with
  dept                                 dept
    MichaelsDepartment : Production       MariasDepartment : Administration
  salary                               salary
    MichaelsSalary : 30000                MariasSalary : 10000
end                                  end

Herbert in Employee with             Edward in Employee with
  dept                                  dept
    HerbertsDepartment : Marketing        EdwardsDepartment : Research
  salary                                salary
    HerbertsSalary : 60000                EdwardsSalary : 50000
end                                  end

3.8

Employee with
constraint
 	salaryIC: $ forall e/Employee m/Manager x,y/Integer
	(e boss m) and (e salary x) and (m salary y) ==> (x <= y) $
end

3.11

QueryClass BossesAndEmployees isA Manager with
computed_attribute
    emps : Employee;
    head_of : Department
constraint
    employee_rule:
       $ (~head_of head this) and (~emps dept ~head_of) $
end