--- a/misc/migration/3.21.2_Any.py	Tue Sep 29 15:15:03 2015 +0200
+++ b/misc/migration/3.21.2_Any.py	Tue Sep 29 15:49:10 2015 +0200
@@ -1,1 +1,7 @@
 sync_schema_props_perms('cwuri')
+
+helper = repo.system_source.dbhelper
+cu = session.cnxset.cu
+helper.set_null_allowed(cu, 'moved_entities', 'extid', 'VARCHAR(256)', False)
+
+commit()