diff --git a/app/but/import_refcomp.py b/app/but/import_refcomp.py
index ae44a34c..9acd1c9d 100644
--- a/app/but/import_refcomp.py
+++ b/app/but/import_refcomp.py
@@ -56,13 +56,13 @@ def orebut_import_refcomp(xml_data: str, dept_id: int, orig_filename=None):
         try:
             c = ApcCompetence(**ApcCompetence.attr_from_xml(competence.attrib))
             db.session.flush()
-        except sqlalchemy.exc.IntegrityError:
+        except sqlalchemy.exc.IntegrityError as exc:
             # ne devrait plus se produire car pas d'unicité de l'id: donc inutile
             db.session.rollback()
             raise ScoValueError(
                 f"""Un référentiel a déjà été chargé avec les mêmes compétences ! ({competence.attrib["id"]})
                 """
-            )
+            ) from exc
         ref.competences.append(c)
         # --- SITUATIONS
         situations = competence.find("situations")
diff --git a/migrations/versions/ee21c76c8183_fix_contrainte_refcomp.py b/migrations/versions/ee21c76c8183_fix_contrainte_refcomp.py
new file mode 100644
index 00000000..0d97b061
--- /dev/null
+++ b/migrations/versions/ee21c76c8183_fix_contrainte_refcomp.py
@@ -0,0 +1,37 @@
+"""Corrige contrainte unicité référentiel compétences
+
+Revision ID: ee21c76c8183
+Revises: c0c225192d61
+Create Date: 2022-06-27 20:18:24.822527
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = "ee21c76c8183"
+down_revision = "c0c225192d61"
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index("ix_apc_competence_id_orebut", table_name="apc_competence")
+    op.create_index(
+        op.f("ix_apc_competence_id_orebut"),
+        "apc_competence",
+        ["id_orebut"],
+        unique=False,
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f("ix_apc_competence_id_orebut"), table_name="apc_competence")
+    op.create_index(
+        "ix_apc_competence_id_orebut", "apc_competence", ["id_orebut"], unique=False
+    )
+    # ### end Alembic commands ###