REM Création des types

1. 
CREATE TYPE adresse_type AS OBJECT
(numero integer,
rue varchar(30),
ville varchar(20))
2.

CREATE TYPE departement_type AS OBJECT
  (numDept smallint, 
   nomDept varchar(20),
   lieu varchar(50)) 


3.
CREATE TYPE employe_type AS OBJECT
   (matricule smallint,
   nom varchar(30),
   adresse adresse_type,
   salaire decimal(8,2),
   superieur ref employe_type,
   departement ref departement_type)
 
4.

REM Création des tables 

create table departement OF departement_type    
  (constraint pk_departement primary key (numDept)) 

create table employe OF employe_type
  (constraint pk_employe primary key (matricule))

5.
describe departement_type

desc employe_type
desc departement
desc employe


6. 
select type_name from user_types