*) Don't apply filter if the term is empty

   see https://github.com/mrjoes/flask-admin/pull/535

flask_admin/contrib/mongoengine/ajax.py

@@ -50,6 +50,7 @@ class QueryAjaxModelLoader(AjaxModelLoader):
     def get_list(self, term, offset=0, limit=DEFAULT_PAGE_SIZE):
         query = self.model.objects
 
+        if len(term) > 0:
             criteria = None
 
             for field in self._cached_fields:

flask_admin/contrib/peewee/ajax.py

@@ -52,6 +52,7 @@ class QueryAjaxModelLoader(AjaxModelLoader):
     def get_list(self, term, offset=0, limit=DEFAULT_PAGE_SIZE):
         query = self.model.select()
 
+        if len(term) > 0:
             stmt = None
             for field in self._cached_fields:
                 q = field ** (u'%%%s%%' % term)

flask_admin/contrib/sqla/ajax.py

@@ -58,6 +58,7 @@ class QueryAjaxModelLoader(AjaxModelLoader):
     def get_list(self, term, offset=0, limit=DEFAULT_PAGE_SIZE):
         query = self.session.query(self.model)
 
+        if len(term) > 0:
             filters = (field.like(u'%%%s%%' % term) for field in self._cached_fields)
             query = query.filter(or_(*filters))