diff --git a/apps/emqx_rule_engine/src/emqx_rule_sqlparser.erl b/apps/emqx_rule_engine/src/emqx_rule_sqlparser.erl
index 03a2e816e..f6db69e44 100644
--- a/apps/emqx_rule_engine/src/emqx_rule_sqlparser.erl
+++ b/apps/emqx_rule_engine/src/emqx_rule_sqlparser.erl
@@ -49,6 +49,10 @@
 
 -export_type([select/0]).
 
+%% Dialyzer gives up on the generated code.
+%% probably due to stack depth, or inlines.
+-dialyzer({nowarn_function, [parse_select/1]}).
+
 %% Parse one select statement.
 -spec(parse_select(string() | binary())
       -> {ok, select()} | {parse_error, term()} | {lex_error, term()}).
@@ -76,7 +80,7 @@ parse_select(Sql) ->
         end
     catch
         _Error:Reason:StackTrace ->
-            {parse_error, Reason, StackTrace}
+            {parse_error, {Reason, StackTrace}}
     end.
 
 -spec(select_fields(select()) -> list(field())).
diff --git a/apps/emqx_rule_engine/src/emqx_rule_sqltester.erl b/apps/emqx_rule_engine/src/emqx_rule_sqltester.erl
index aeb1bf588..bedfe324e 100644
--- a/apps/emqx_rule_engine/src/emqx_rule_sqltester.erl
+++ b/apps/emqx_rule_engine/src/emqx_rule_sqltester.erl
@@ -21,24 +21,30 @@
 -export([ test/1
         ]).
 
+%% Dialyzer gives up on the generated code.
+%% probably due to stack depth, or inlines.
+-dialyzer({nowarn_function, [test/1,
+                             test_rule/4,
+                             flatten/1,
+                             sql_test_action/0,
+                             fill_default_values/2
+                             ]}).
+
 -spec(test(#{}) -> {ok, Result::map()} | no_return()).
 test(#{<<"rawsql">> := Sql, <<"ctx">> := Context}) ->
-    case emqx_rule_sqlparser:parse_select(Sql) of
-        {ok, Select} ->
-            InTopic = maps:get(<<"topic">>, Context, <<>>),
-            EventTopics = emqx_rule_sqlparser:select_from(Select),
-            case lists:all(fun is_publish_topic/1, EventTopics) of
-                true ->
-                    %% test if the topic matches the topic filters in the rule
-                    case emqx_rule_utils:can_topic_match_oneof(InTopic, EventTopics) of
-                        true -> test_rule(Sql, Select, Context, EventTopics);
-                        false -> {error, nomatch}
-                    end;
-                false ->
-                    %% the rule is for both publish and events, test it directly
-                    test_rule(Sql, Select, Context, EventTopics)
+    {ok, Select} = emqx_rule_sqlparser:parse_select(Sql),
+    InTopic = maps:get(<<"topic">>, Context, <<>>),
+    EventTopics = emqx_rule_sqlparser:select_from(Select),
+    case lists:all(fun is_publish_topic/1, EventTopics) of
+        true ->
+            %% test if the topic matches the topic filters in the rule
+            case emqx_rule_utils:can_topic_match_oneof(InTopic, EventTopics) of
+                true -> test_rule(Sql, Select, Context, EventTopics);
+                false -> {error, nomatch}
             end;
-        Error -> error(Error)
+        false ->
+            %% the rule is for both publish and events, test it directly
+            test_rule(Sql, Select, Context, EventTopics)
     end.
 
 test_rule(Sql, Select, Context, EventTopics) ->