diff --git a/apps/emqx_authz/test/emqx_authz_redis_SUITE.erl b/apps/emqx_authz/test/emqx_authz_redis_SUITE.erl
index ebf2b4d06..54d7a406c 100644
--- a/apps/emqx_authz/test/emqx_authz_redis_SUITE.erl
+++ b/apps/emqx_authz/test/emqx_authz_redis_SUITE.erl
@@ -161,12 +161,13 @@ t_lookups(_Config) ->
         ]
     ).
 
-t_create_invalid(_Config) ->
+%% should still succeed to create even if the config will not work,
+%% because it's not a part of the schema check
+t_create_with_config_values_wont_works(_Config) ->
     AuthzConfig = raw_redis_authz_config(),
 
     InvalidConfigs =
         [
-            maps:without([<<"server">>], AuthzConfig),
             AuthzConfig#{<<"server">> => <<"unknownhost:3333">>},
             AuthzConfig#{<<"password">> => <<"wrongpass">>},
             AuthzConfig#{<<"database">> => <<"5678">>}
@@ -180,6 +181,15 @@ t_create_invalid(_Config) ->
         InvalidConfigs
     ).
 
+%% creating without a require filed should return error
+t_create_invalid_schema(_Config) ->
+    AuthzConfig = raw_redis_authz_config(),
+    C = maps:without([<<"server">>], AuthzConfig),
+    ?assertMatch(
+        {error, {emqx_conf_schema, _}},
+        emqx_authz:update(?CMD_REPLACE, [C])
+    ).
+
 t_redis_error(_Config) ->
     ok = setup_config(#{<<"cmd">> => <<"INVALID COMMAND">>}),
 
diff --git a/apps/emqx_resource/src/emqx_resource_validator.erl b/apps/emqx_resource/src/emqx_resource_validator.erl
index 7623ae7fa..a5404a65e 100644
--- a/apps/emqx_resource/src/emqx_resource_validator.erl
+++ b/apps/emqx_resource/src/emqx_resource_validator.erl
@@ -30,6 +30,7 @@ min(Type, Min) ->
 
 not_empty(ErrMsg) ->
     fun
+        (undefined) -> {error, ErrMsg};
         (<<>>) -> {error, ErrMsg};
         (_) -> ok
     end.