diff --git a/scripts-available/CDB_Username.sql b/scripts-available/CDB_Username.sql
index 9a747ed..9c6a5bc 100644
--- a/scripts-available/CDB_Username.sql
+++ b/scripts-available/CDB_Username.sql
@@ -1,13 +1,6 @@
--- Function returning the username of the provided user
-CREATE OR REPLACE FUNCTION _CDB_Username(pg_user TEXT)
-RETURNS text
-AS $$
-  SELECT CDB_Conf_GetConf(CONCAT('api_keys_', pg_user))->>'username';
-$$ LANGUAGE SQL STRICT IMMUTABLE PARALLEL SAFE SECURITY DEFINER;
-
--- Function returning the username of the current user
+-- Returns the cartodb username of the current PostgreSQL session
 CREATE OR REPLACE FUNCTION CDB_Username()
 RETURNS text
 AS $$
-  SELECT _CDB_Username(current_user);
-$$ LANGUAGE SQL STABLE PARALLEL SAFE;
+  SELECT CDB_Conf_GetConf(CONCAT('api_keys_', session_user))->>'username';
+$$ LANGUAGE SQL STABLE PARALLEL SAFE SECURITY DEFINER;
diff --git a/test/CDB_Username.sql b/test/CDB_Username.sql
index 1d187e2..ed344d6 100644
--- a/test/CDB_Username.sql
+++ b/test/CDB_Username.sql
@@ -1,24 +1,22 @@
-SELECT current_user; -- postgres
+SELECT session_user; -- postgres
 SELECT CDB_Username(); -- (NULL)
 
--- Add the role fulano with an api_key and connect with it
+-- Add the role fulano with api_key and connect with it
 \set QUIET on
 CREATE ROLE fulano LOGIN;
 GRANT USAGE ON SCHEMA cartodb TO fulano;
 GRANT EXECUTE ON FUNCTION CDB_Username() TO fulano;
-GRANT EXECUTE ON FUNCTION _CDB_Username(text) TO fulano;
 INSERT INTO cdb_conf (key, value) VALUES ('api_keys_fulano', '{"username": "fulanito", "permissions":[]}');
-SET ROLE fulano;
+SET SESSION AUTHORIZATION fulano;
 \set QUIET off
 
-SELECT current_user; -- fulano
+SELECT session_user; -- fulano
 SELECT CDB_Username(); -- fulanito
 
 -- Remove fulano
 \set QUIET on
-SET ROLE postgres;
+SET SESSION AUTHORIZATION postgres;
 REVOKE USAGE ON SCHEMA cartodb FROM fulano;
 REVOKE EXECUTE ON FUNCTION CDB_Username() FROM fulano;
-REVOKE EXECUTE ON FUNCTION _CDB_Username(text) FROM fulano;
 DROP ROLE fulano;
-\set QUIET off
+\set QUIET off
\ No newline at end of file