SELECT @@GLOBAL.innodb_max_purge_lag_delay; @@GLOBAL.innodb_max_purge_lag_delay 0 0 Expected SET @@GLOBAL.innodb_max_purge_lag_delay=1; SELECT COUNT(@@GLOBAL.innodb_max_purge_lag_delay); COUNT(@@GLOBAL.innodb_max_purge_lag_delay) 1 1 Expected SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES WHERE VARIABLE_NAME='innodb_max_purge_lag_delay'; VARIABLE_VALUE 1 1 Expected SELECT @@innodb_max_purge_lag_delay = @@GLOBAL.innodb_max_purge_lag_delay; @@innodb_max_purge_lag_delay = @@GLOBAL.innodb_max_purge_lag_delay 1 1 Expected SELECT COUNT(@@innodb_max_purge_lag_delay); COUNT(@@innodb_max_purge_lag_delay) 1 1 Expected SELECT COUNT(@@local.innodb_max_purge_lag_delay); ERROR HY000: Variable 'innodb_max_purge_lag_delay' is a GLOBAL variable Expected error 'Variable is a GLOBAL variable' SELECT COUNT(@@SESSION.innodb_max_purge_lag_delay); ERROR HY000: Variable 'innodb_max_purge_lag_delay' is a GLOBAL variable Expected error 'Variable is a GLOBAL variable' SELECT innodb_max_purge_lag_delay = @@SESSION.innodb_max_purge_lag_delay; ERROR 42S22: Unknown column 'innodb_max_purge_lag_delay' in 'field list' set global innodb_max_purge_lag_delay = -1; Warnings: Warning 1292 Truncated incorrect innodb_max_purge_lag_delay value: '-1' set global innodb_max_purge_lag_delay = 1000000; set global innodb_max_purge_lag_delay = 10000000; set global innodb_max_purge_lag_delay = 100000000; Warnings: Warning 1292 Truncated incorrect innodb_max_purge_lag_delay value: '100000000' set global innodb_max_purge_lag_delay = 100000001; Warnings: Warning 1292 Truncated incorrect innodb_max_purge_lag_delay value: '100000001' set global innodb_max_purge_lag_delay = 0;