Hi, I have a new db user created by following scripts: CREATE USER "imdb" WITH PASSWORD 'imdb' NAME 'IMDB Explorer' SCHEMA "sys"; CREATE SCHEMA "imdb" AUTHORIZATION "imdb"; ALTER USER "imdb" SET SCHEMA "imdb"; When I tried to execute the function "timestamp_to_str", I have to add "sys." prefix to make it effective. "date_trunc" also needed to do so. The default user "monetdb" can run the function directly without the prefix. What should I do to perform the same way as user "monetdb" ? sql>select timestamp_to_str(localtimestamp, '%Y-%m-%d %H:%M:%S %z'); SELECT: no such binary operator 'timestamp_to_str(timestamp,char)' sql>select sys.timestamp_to_str(localtimestamp, '%Y-%m-%d %H:%M:%S %z'); +---------------------------+ | L2 | +===========================+ | 2020-04-06 20:37:39 +0800 | +---------------------------+ 1 tuple sql>select date_trunc('minute', timestamp '2119-02-17 02:08:12.345678'); SELECT: no such binary operator 'date_trunc(char,timestamp)' sql>select sys.date_trunc('minute', timestamp '2119-02-17 02:08:12.345678'); +----------------------------+ | L2 | +============================+ | 2119-02-17 02:08:00.000000 | +----------------------------+ 1 tuple