diff --git a/app/models/formations.py b/app/models/formations.py
index 942e1a9b..45f42d29 100644
--- a/app/models/formations.py
+++ b/app/models/formations.py
@@ -43,6 +43,13 @@ class Formation(db.Model):
     def __repr__(self):
         return f"<{self.__class__.__name__}(id={self.id}, dept_id={self.dept_id}, acronyme='{self.acronyme}')>"
 
+    def to_dict(self):
+        e = dict(self.__dict__)
+        e.pop("_sa_instance_state", None)
+        # ScoDoc7 output_formators: (backward compat)
+        e["formation_id"] = self.id
+        return e
+
     def get_parcours(self):
         """get l'instance de TypeParcours de cette formation"""
         return sco_codes_parcours.get_parcours_from_code(self.type_parcours)
@@ -215,6 +222,19 @@ class Module(db.Model):
             f"<Module{ModuleType(self.module_type).name} id={self.id} code={self.code}>"
         )
 
+    def to_dict(self):
+        e = dict(self.__dict__)
+        e.pop("_sa_instance_state", None)
+        # ScoDoc7 output_formators: (backward compat)
+        e["module_id"] = self.id
+        e["heures_cours"] = 0.0 if self.heures_cours is None else self.heures_cours
+        e["heures_td"] = 0.0 if self.heures_td is None else self.heures_td
+        e["heures_tp"] = 0.0 if self.heures_tp is None else self.heures_tp
+        e["numero"] = 0 if self.numero is None else self.numero
+        e["coefficient"] = 0.0 if self.coefficient is None else self.coefficient
+        e["module_type"] = 0 if self.module_type is None else self.module_type
+        return e
+
     def is_apc(self):
         "True si module SAÉ ou Ressource"
         return scu.ModuleType(self.module_type) in {
@@ -274,20 +294,34 @@ class ModuleUECoef(db.Model):
     __tablename__ = "module_ue_coef"
 
     module_id = db.Column(
-        db.Integer, db.ForeignKey("notes_modules.id"), primary_key=True
+        db.Integer,
+        db.ForeignKey("notes_modules.id", ondelete="CASCADE"),
+        primary_key=True,
+    )
+    ue_id = db.Column(
+        db.Integer,
+        db.ForeignKey("notes_ue.id", ondelete="CASCADE"),
+        primary_key=True,
     )
-    ue_id = db.Column(db.Integer, db.ForeignKey("notes_ue.id"), primary_key=True)
     coef = db.Column(
         db.Float,
         nullable=False,
     )
     module = db.relationship(
         Module,
-        backref=db.backref("ue_coefs", cascade="all, delete-orphan"),
+        backref=db.backref(
+            "ue_coefs",
+            passive_deletes=True,
+            cascade="save-update, merge, delete, delete-orphan",
+        ),
     )
     ue = db.relationship(
         UniteEns,
-        backref=db.backref("module_ue_coefs", cascade="all, delete-orphan"),
+        backref=db.backref(
+            "module_ue_coefs",
+            passive_deletes=True,
+            cascade="save-update, merge, delete, delete-orphan",
+        ),
     )
 
 
diff --git a/migrations/versions/a26b3103697d_fix_cascades_on_moduleuecoef.py b/migrations/versions/a26b3103697d_fix_cascades_on_moduleuecoef.py
new file mode 100644
index 00000000..38d4d497
--- /dev/null
+++ b/migrations/versions/a26b3103697d_fix_cascades_on_moduleuecoef.py
@@ -0,0 +1,64 @@
+"""fix cascades on ModuleUECoef
+
+Revision ID: a26b3103697d
+Revises: c8efc54586d8
+Create Date: 2021-11-30 10:47:23.465897
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = "a26b3103697d"
+down_revision = "c8efc54586d8"
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_constraint(
+        "module_ue_coef_module_id_fkey", "module_ue_coef", type_="foreignkey"
+    )
+    op.drop_constraint(
+        "module_ue_coef_ue_id_fkey", "module_ue_coef", type_="foreignkey"
+    )
+    op.create_foreign_key(
+        "ev_module_ue_coef_ue_id_fkey",
+        "module_ue_coef",
+        "notes_modules",
+        ["module_id"],
+        ["id"],
+        ondelete="CASCADE",
+    )
+    op.create_foreign_key(
+        "ev_module_ue_coef_module_id_fkey",
+        "module_ue_coef",
+        "notes_ue",
+        ["ue_id"],
+        ["id"],
+        ondelete="CASCADE",
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_constraint(
+        "ev_module_ue_coef_ue_id_fkey", "module_ue_coef", type_="foreignkey"
+    )
+    op.drop_constraint(
+        "ev_module_ue_coef_module_id_fkey", "module_ue_coef", type_="foreignkey"
+    )
+    op.create_foreign_key(
+        "module_ue_coef_ue_id_fkey", "module_ue_coef", "notes_ue", ["ue_id"], ["id"]
+    )
+    op.create_foreign_key(
+        "module_ue_coef_module_id_fkey",
+        "module_ue_coef",
+        "notes_modules",
+        ["module_id"],
+        ["id"],
+    )
+    # ### end Alembic commands ###