diff --git a/tryton/trytond/trytond/pool.py b/trytond/trytond/pool.py
index a21e9e63e8..bd22d3b073 100644
--- a/tryton/trytond/trytond/pool.py
+++ b/tryton/trytond/trytond/pool.py
@@ -197,6 +197,16 @@ class Pool(object):
                 self.add(cls, type)
                 self.setup_mixin(self._modules, type='report', name=name)
                 return self.get(name, type=type)
+            elif name[:15] == 'babi_execution_':
+                import sys
+                # Do not reload if babi model is accessed during update.
+                if not sys.argv[0].endswith('trytond-admin'):
+                    with Transaction(new=True).start(self.database_name, 0,
+                            readonly=False):
+                        Execution = self.get('babi.report.execution')
+                        execution = Execution(int(name[15:]))
+                        execution.validate_model(avoid_registration=True)
+                    return self._pool[self.database_name][type][name]
             raise
 
     def add(self, cls, type='model'):
diff --git a/tryton/trytond/trytond/model/modelsql.py b/tryton/trytond/trytond/model/modelsql.py
index a21e9e63e8..e767d2e9ae 100644
--- a/tryton/trytond/trytond/model/modelsql.py
+++ b/tryton/trytond/trytond/model/modelsql.py
@@ -747,13 +747,21 @@ class ModelSQL(ModelStorage):
         extra_fields = set()
         if 'write_date' not in fields_names:
             extra_fields.add('write_date')
+        fields_names = fields_names[:]
         for field_name in fields_names:
             if field_name in {'_timestamp', '_write', '_delete'}:
                 continue
             if '.' in field_name:
                 field_name, field_related = field_name.split('.', 1)
                 fields_related[field_name].add(field_related)
-            field = cls._fields[field_name]
+            try:
+                field = cls._fields[field_name]
+            except KeyError as err:
+                if 'babi_' in str(err):
+                    fields_names.remove(field_name)
+                    continue
+                else:
+                    raise
             if hasattr(field, 'datetime_field') and field.datetime_field:
                 extra_fields.add(field.datetime_field)
             if field.context:
@@ -1209,8 +1217,14 @@ class ModelSQL(ModelStorage):
                 foreign_table = Model.__table__()
                 foreign_red_sql = reduce_ids(
                     Column(foreign_table, field_name), sub_ids)
-                cursor.execute(*foreign_table.select(foreign_table.id,
-                        where=foreign_red_sql))
+                import psycopg2
+                try:
+                    cursor.execute(*foreign_table.select(foreign_table.id,
+                            where=foreign_red_sql))
+                except psycopg2.errors.UndefinedTable as ex:
+                    if ex.args and (len(ex.args) > 0) and 'babi_execution' in ex.args[0]:
+                        return []
+                    raise
                 related_records = Model.browse([x[0] for x in cursor])
             else:
                 with transaction.set_context(active_test=False):
diff --git a/tryton/trytond/trytond/ir/model.py b/tryton/trytond/trytond/ir/model.py
index 6304018f24..1ea08d8be5 100644
--- a/tryton/trytond/trytond/ir/model.py
+++ b/tryton/trytond/trytond/ir/model.py
@@ -555,8 +555,14 @@ class ModelAccess(DeactivableMixin, ModelSQL, ModelView):
                 fill_models(field.get_target(), models)
         model2models = defaultdict(list)
         for model in models:
-            fill_models(pool.get(model), model2models[model])
-
+            try:
+                fill_models(pool.get(model), model2models[model])
+            except KeyError as err:
+                if 'babi_execution_' in str(err):
+                    models.remove(model)
+                    continue
+                else:
+                    raise
         all_models = list(set(sum(model2models.values(), [])))
         default = {'read': True, 'write': True, 'create': True, 'delete': True}
         default_singleton = {