diff --git a/odoo/models.py b/odoo/models.py
index bb1c305daa2..ddc6a518acc 100644
--- a/odoo/models.py
+++ b/odoo/models.py
@@ -940,6 +940,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
             batch.clear()
             batch_xml_ids.clear()
 
+            unknown_msg = _(u"Unknown database error: '%s'")
             try:
                 cr.execute('SAVEPOINT model_load_save')
             except psycopg2.InternalError as e:
@@ -947,7 +948,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
                 # already logged
                 if not any(message['type'] == 'error' for message in messages):
                     info = data_list[0]['info']
-                    messages.append(dict(info, type='error', message=u"Unknown database error: '%s'" % e))
+                    messages.append(dict(info, type='error', message=unknown_msg % e))
                 return
 
             # try to create in batch
@@ -6212,8 +6213,8 @@ def convert_pgerror_not_null(model, fields, info, e):
 def convert_pgerror_unique(model, fields, info, e):
     # new cursor since we're probably in an error handler in a blown
     # transaction which may not have been rollbacked/cleaned yet
-    with closing(model.env.registry.cursor()) as cr:
-        cr.execute("""
+    with closing(model.env.registry.cursor()) as cr_tmp:
+        cr_tmp.execute("""
             SELECT
                 conname AS "constraint name",
                 t.relname AS "table name",
@@ -6226,7 +6227,7 @@ def convert_pgerror_unique(model, fields, info, e):
             JOIN pg_class t ON t.oid = conrelid
             WHERE conname = %s
         """, [e.diag.constraint_name])
-        constraint, table, ufields = cr.fetchone() or (None, None, None)
+        constraint, table, ufields = cr_tmp.fetchone() or (None, None, None)
     # if the unique constraint is on an expression or on an other table
     if not ufields or model._table != table:
         return {'message': tools.ustr(e)}