SET GLOBAL log_error_services='';
Warnings:
Warning	3702	Setting an empty log_error_services pipeline disables error logging!
SET GLOBAL log_error_services=NULL;
ERROR 42000: Variable 'log_error_services' can't be set to the value of 'NULL'
SET GLOBAL log_error_services=DEFAULT;
SELECT @@global.log_error_services;
@@global.log_error_services
log_filter_internal; log_sink_internal