diff --git a/ITPlanning/db.py b/ITPlanning/db.py
index c5ff613..7fa8bc9 100644
--- a/ITPlanning/db.py
+++ b/ITPlanning/db.py
@@ -59,6 +59,7 @@ class Customer(db.Entity):
     tickets = Set("Ticket")
     appointments = Set(Appointment)
     notes = Optional(str)
+    planner = Optional("Planner")
 
 
 class Ticket(db.Entity):
@@ -66,7 +67,7 @@ class Ticket(db.Entity):
     ref = Optional(str, unique=True)
     service_category = Required("Service_category")
     customer = Required(Customer)
-    appointment = Required(Appointment)
+    appointment = Optional(Appointment)
     notes = Optional(str)
 
 
@@ -80,10 +81,11 @@ class Service_category(db.Entity):
     description = Optional(str)
 
 
-class Planner(Customer):
+class Planner(db.Entity):
     plannings = Set(Planning)
     password = Required(str)
     is_admin = Optional(bool)
+    customer = Required(Customer)
 
 
 def parse_uri(database_uri):