diff --git a/superset/viz.py b/superset/viz.py
index 61fd4ed557a6..b880646491ca 100755
--- a/superset/viz.py
+++ b/superset/viz.py
@@ -119,7 +119,8 @@ def get_df(self, query_obj=None):
         # parsing logic.
         if df is None or df.empty:
             self.status = utils.QueryStatus.FAILED
-            self.error_message = "No data."
+            if not self.error_message:
+                self.error_message = "No data."
             return pd.DataFrame()
         else:
             if DTTM_ALIAS in df.columns: