select @@global.relay_log_info_file; @@global.relay_log_info_file relay-log.info select @@session.relay_log_info_file; ERROR HY000: Variable 'relay_log_info_file' is a GLOBAL variable show global variables like 'relay_log_info_file'; Variable_name Value relay_log_info_file relay-log.info show session variables like 'relay_log_info_file'; Variable_name Value relay_log_info_file relay-log.info select * from information_schema.global_variables where variable_name='relay_log_info_file'; VARIABLE_NAME VARIABLE_VALUE RELAY_LOG_INFO_FILE relay-log.info select * from information_schema.session_variables where variable_name='relay_log_info_file'; VARIABLE_NAME VARIABLE_VALUE RELAY_LOG_INFO_FILE relay-log.info set global relay_log_info_file=1; ERROR HY000: Variable 'relay_log_info_file' is a read only variable set session relay_log_info_file=1; ERROR HY000: Variable 'relay_log_info_file' is a read only variable