Only rebuild mptt tree one time per model in a database update

issue5118
review20501002

trytond/model/modelsql.py

@@ -128,6 +128,8 @@ class ModelSQL(ModelStorage):
     def __register__(cls, module_name):
         TableHandler = backend.get('TableHandler')
         super(ModelSQL, cls).__register__(module_name)
+        pool = Pool()
+        ModelField = pool.get('ir.model.field')
 
         if cls.table_query():
             return
@@ -205,7 +207,13 @@ class ModelSQL(ModelStorage):
             if isinstance(field, fields.Many2One) \
                     and field.model_name == cls.__name__ \
                     and field.left and field.right:
-                cls._rebuild_tree(field_name, None, 0)
+                irfields = ModelField.search([
+                        ('model.model', '=', field.model_name),
+                        ('module', '=', module_name),
+                        ('name', 'in', [field.left, field.right]),
+                        ])
+                if irfields:
+                    cls._rebuild_tree(field_name, None, 0)
 
         for ident, constraint, _ in cls._sql_constraints:
             table.add_constraint(ident, constraint)