diff --git a/pydruid/db/sqlalchemy.py b/pydruid/db/sqlalchemy.py
index 76b7a3c1..42336fb7 100644
--- a/pydruid/db/sqlalchemy.py
+++ b/pydruid/db/sqlalchemy.py
@@ -123,8 +123,8 @@ def do_ping(self, dbapi_connection) -> bool:
         Return if the database can be reached.
         """
         try:
-            dbapi_connection.execute(text("SELECT 1"))
-        except Exception as ex:
+            dbapi_connection.execute("SELECT 1")
+        except Exception:
             return False
 
         return True
diff --git a/pydruid/query.py b/pydruid/query.py
index f95209d1..df2955e9 100644
--- a/pydruid/query.py
+++ b/pydruid/query.py
@@ -246,6 +246,8 @@ def parse_datasource(datasource, query_type):
                 "Datasource definition not valid. Must be string or "
                 "dict or list of strings"
             )
+        if isinstance(datasource, list):
+            return {"type": "union", "dataSources": datasource}
         return datasource
 
     @staticmethod
diff --git a/tests/db/test_cursor.py b/tests/db/test_cursor.py
index a98d3335..dede75fd 100644
--- a/tests/db/test_cursor.py
+++ b/tests/db/test_cursor.py
@@ -355,7 +355,7 @@ def test_ssl_client_cert_authentication_with_patch_imported(
             ANY,
             stream=True,
             headers={"Content-Type": "application/json"},
-            json={"query": "SELECT * FROM table", "context": {}, "header": False},
+            json={"query": "SELECT * FROM table", "context": {}, "header": True},
             auth=ANY,
             verify=True,
             cert="path/to/cert",