select @@global.relay_log_recovery; @@global.relay_log_recovery 0 select @@session.relay_log_recovery; ERROR HY000: Variable 'relay_log_recovery' is a GLOBAL variable show global variables like 'relay_log_recovery'; Variable_name Value relay_log_recovery OFF show session variables like 'relay_log_recovery'; Variable_name Value relay_log_recovery OFF select * from information_schema.global_variables where variable_name='relay_log_recovery'; VARIABLE_NAME VARIABLE_VALUE RELAY_LOG_RECOVERY OFF select * from information_schema.session_variables where variable_name='relay_log_recovery'; VARIABLE_NAME VARIABLE_VALUE RELAY_LOG_RECOVERY OFF set global relay_log_recovery=1; ERROR HY000: Variable 'relay_log_recovery' is a read only variable select @@global.relay_log_recovery; @@global.relay_log_recovery 0 select * from information_schema.global_variables where variable_name='relay_log_recovery'; VARIABLE_NAME VARIABLE_VALUE RELAY_LOG_RECOVERY OFF select * from information_schema.session_variables where variable_name='relay_log_recovery'; VARIABLE_NAME VARIABLE_VALUE RELAY_LOG_RECOVERY OFF