1select @@global.report_user; 2@@global.report_user 3NULL 4select @@session.report_user; 5ERROR HY000: Variable 'report_user' is a GLOBAL variable 6show global variables like 'report_user'; 7Variable_name Value 8report_user 9show session variables like 'report_user'; 10Variable_name Value 11report_user 12select * from information_schema.global_variables where variable_name='report_user'; 13VARIABLE_NAME VARIABLE_VALUE 14REPORT_USER 15select * from information_schema.session_variables where variable_name='report_user'; 16VARIABLE_NAME VARIABLE_VALUE 17REPORT_USER 18set global report_user=1; 19ERROR HY000: Variable 'report_user' is a read only variable 20set session report_user=1; 21ERROR HY000: Variable 'report_user' is a read only variable 22