diff --git a/oslo_db/sqlalchemy/engines.py b/oslo_db/sqlalchemy/engines.py
index 25215b96..0e19c183 100644
--- a/oslo_db/sqlalchemy/engines.py
+++ b/oslo_db/sqlalchemy/engines.py
@@ -105,6 +105,14 @@ def _setup_logging(connection_debug=0):
 
 
 def _extend_url_parameters(url, connection_parameters):
+    # TODO(zzzeek): remove hasattr() conditional when SQLAlchemy 1.4 is the
+    # minimum version in requirements; call update_query_string()
+    # unconditionally
+    if hasattr(url, "update_query_string"):
+        return url.update_query_string(connection_parameters, append=True)
+
+    # TODO(zzzeek): remove the remainder of this method when SQLAlchemy 1.4
+    # is the minimum version in requirements
     for key, value in parse.parse_qs(
             connection_parameters).items():
         if key in url.query:
@@ -118,6 +126,8 @@ def _extend_url_parameters(url, connection_parameters):
         if len(value) == 1:
             url.query[key] = value[0]
 
+    return url
+
 
 def _vet_url(url):
     if "+" not in url.drivername and not url.drivername.startswith("sqlite"):
@@ -153,7 +163,7 @@ def create_engine(sql_connection, sqlite_fk=False, mysql_sql_mode=None,
     url = sqlalchemy.engine.url.make_url(sql_connection)
 
     if connection_parameters:
-        _extend_url_parameters(url, connection_parameters)
+        url = _extend_url_parameters(url, connection_parameters)
 
     _vet_url(url)
 
diff --git a/oslo_db/sqlalchemy/provision.py b/oslo_db/sqlalchemy/provision.py
index 2fc3a543..5addab45 100644
--- a/oslo_db/sqlalchemy/provision.py
+++ b/oslo_db/sqlalchemy/provision.py
@@ -495,7 +495,16 @@ class BackendImpl(object, metaclass=abc.ABCMeta):
         """
 
         url = sa_url.make_url(str(base_url))
-        url.database = ident
+
+        # TODO(zzzeek): remove hasattr() conditional in favor of "url.set()"
+        # when SQLAlchemy 1.4 is the minimum version in requirements
+        if hasattr(url, "set"):
+            url = url.set(database=ident)
+        else:
+            # TODO(zzzeek): remove when SQLAlchemy 1.4
+            # is the minimum version in requirements
+            url.database = ident
+
         return url
 
 
diff --git a/oslo_db/tests/sqlalchemy/test_exc_filters.py b/oslo_db/tests/sqlalchemy/test_exc_filters.py
index b7e0f910..49826e0b 100644
--- a/oslo_db/tests/sqlalchemy/test_exc_filters.py
+++ b/oslo_db/tests/sqlalchemy/test_exc_filters.py
@@ -386,8 +386,16 @@ class TestNonExistentDatabase(
         super(TestNonExistentDatabase, self).setUp()
 
         url = sqla_url.make_url(str(self.engine.url))
-        url.database = 'non_existent_database'
-        self.url = url
+
+        # TODO(zzzeek): remove hasattr() conditional in favor of "url.set()"
+        # when SQLAlchemy 1.4 is the minimum version in requirements
+        if hasattr(url, "set"):
+            self.url = url.set(database="non_existent_database")
+        else:
+            # TODO(zzzeek): remove when SQLAlchemy 1.4
+            # is the minimum version in requirements
+            url.database = 'non_existent_database'
+            self.url = url
 
     def test_raise(self):
         matched = self.assertRaises(
diff --git a/oslo_db/tests/sqlalchemy/test_sqlalchemy.py b/oslo_db/tests/sqlalchemy/test_sqlalchemy.py
index 8a48ecab..7b51e360 100644
--- a/oslo_db/tests/sqlalchemy/test_sqlalchemy.py
+++ b/oslo_db/tests/sqlalchemy/test_sqlalchemy.py
@@ -229,6 +229,16 @@ class QueryParamTest(test_base.DbTestCase):
             "oslo_db.sqlalchemy.engines.sqlalchemy.create_engine",
             side_effect=_mock_create_engine)
 
+    def _normalize_query_dict(self, qdict):
+        # SQLAlchemy 1.4 returns url.query as:
+        # immutabledict({k1: v1, k2: (v2a, v2b, ...), ...})
+        # that is with tuples not lists for multiparams
+
+        return {
+            k: list(v) if isinstance(v, tuple) else v
+            for k, v in qdict.items()
+        }
+
     def test_add_assorted_params(self):
         with self._fixture() as ce:
             engines.create_engine(
@@ -236,7 +246,7 @@ class QueryParamTest(test_base.DbTestCase):
                 connection_parameters="foo=bar&bat=hoho&bat=param2")
 
         self.assertEqual(
-            ce.mock_calls[0][1][0].query,
+            self._normalize_query_dict(ce.mock_calls[0][1][0].query),
             {'bat': ['hoho', 'param2'], 'foo': 'bar'}
         )
 
@@ -247,7 +257,7 @@ class QueryParamTest(test_base.DbTestCase):
 
         self.assertEqual(
             ce.mock_calls[0][1][0].query,
-            {}
+            self._normalize_query_dict({})
         )
 
     def test_combine_params(self):
@@ -260,7 +270,7 @@ class QueryParamTest(test_base.DbTestCase):
                                       "bind_host=192.168.1.5")
 
         self.assertEqual(
-            ce.mock_calls[0][1][0].query,
+            self._normalize_query_dict(ce.mock_calls[0][1][0].query),
             {
                 'bind_host': '192.168.1.5',
                 'charset': 'utf8',
@@ -280,7 +290,7 @@ class QueryParamTest(test_base.DbTestCase):
                                       "bind_host=192.168.1.5")
 
         self.assertEqual(
-            ce.mock_calls[0][1][0].query,
+            self._normalize_query_dict(ce.mock_calls[0][1][0].query),
             {
                 'bind_host': '192.168.1.5',
                 'charset': 'utf8',
@@ -751,7 +761,7 @@ class CreateEngineTest(oslo_test.BaseTestCase):
         def warn_interpolate(msg, args):
             # test the interpolation itself to ensure the password
             # is concealed
-            warnings.warning(msg % args)
+            warnings.warning(msg % (args, ))
 
         with mock.patch(
                 "oslo_db.sqlalchemy.engines.LOG.warning",