diff --git a/superset/templates/superset/models/database/macros.html b/superset/templates/superset/models/database/macros.html
index f6a054e455..ae67e4b78f 100644
--- a/superset/templates/superset/models/database/macros.html
+++ b/superset/templates/superset/models/database/macros.html
@@ -41,12 +41,12 @@
           uri: $.trim($("#sqlalchemy_uri").val()),
           name: $('#database_name').val(),
           impersonate_user: $('#impersonate_user').is(':checked'),
-          extras: extra ? JSON.parse(extra) : {},
+          extra: extra ? JSON.parse(extra) : {},
           encrypted_extra: encryptedExtra ? JSON.parse(encryptedExtra) : {},
           server_cert: $("#server_cert").val(),
         })
       } catch(parse_error){
-        alert("Malformed JSON in the extras field: " + parse_error);
+        alert("Malformed JSON in the extra fields: " + parse_error);
         return false
       }
 
diff --git a/superset/views/core.py b/superset/views/core.py
index c6847b7132..9f16f85c36 100755
--- a/superset/views/core.py
+++ b/superset/views/core.py
@@ -1135,12 +1135,11 @@ class Superset(BaseSupersetView):  # pylint: disable=too-many-public-methods
                 if existing_database and uri == existing_database.safe_sqlalchemy_uri():
                     uri = existing_database.sqlalchemy_uri_decrypted
 
-            # this is the database instance that will be tested
+            # This is the database instance that will be tested. Note the extra fields
+            # are represented as JSON encoded strings in the model.
             database = models.Database(
-                # extras is sent as json, but required to be a string in the Database
-                # model
                 server_cert=request.json.get("server_cert"),
-                extra=json.dumps(request.json.get("extras", {})),
+                extra=json.dumps(request.json.get("extra", {})),
                 impersonate_user=request.json.get("impersonate_user"),
                 encrypted_extra=json.dumps(request.json.get("encrypted_extra", {})),
             )