diff --git a/redash/query_runner/elasticsearch.py b/redash/query_runner/elasticsearch.py
index 825cec0eb7..2e70e4672c 100644
--- a/redash/query_runner/elasticsearch.py
+++ b/redash/query_runner/elasticsearch.py
@@ -123,8 +123,8 @@ def _get_query_mappings(self, url):
         if error:
             return mappings, error
 
-        for index_name in mappings_data:
-            index_mappings = mappings_data[index_name]
+        for index_name in mappings:
+            index_mappings = mappings[index_name]
             for m in index_mappings.get("mappings", {}):
                 for property_name in index_mappings["mappings"][m]["properties"]:
                     property_data = index_mappings["mappings"][m]["properties"][property_name]