1SET @start_global_value = @@global.innodb_instant_alter_column_allowed; 2SET GLOBAL innodb_instant_alter_column_allowed=never; 3select @@session.innodb_instant_alter_column_allowed; 4ERROR HY000: Variable 'innodb_instant_alter_column_allowed' is a GLOBAL variable 5show global variables like 'innodb_instant_alter_column_allowed'; 6Variable_name Value 7innodb_instant_alter_column_allowed never 8show session variables like 'innodb_instant_alter_column_allowed'; 9Variable_name Value 10innodb_instant_alter_column_allowed never 11SELECT * FROM information_schema.global_variables 12WHERE variable_name='innodb_instant_alter_column_allowed'; 13VARIABLE_NAME VARIABLE_VALUE 14INNODB_INSTANT_ALTER_COLUMN_ALLOWED never 15SELECT * FROM information_schema.session_variables 16WHERE variable_name='innodb_instant_alter_column_allowed'; 17VARIABLE_NAME VARIABLE_VALUE 18INNODB_INSTANT_ALTER_COLUMN_ALLOWED never 19set global innodb_instant_alter_column_allowed=no; 20ERROR 42000: Variable 'innodb_instant_alter_column_allowed' can't be set to the value of 'no' 21set global innodb_instant_alter_column_allowed=1.1; 22ERROR 42000: Incorrect argument type to variable 'innodb_instant_alter_column_allowed' 23set global innodb_instant_alter_column_allowed=-1; 24ERROR 42000: Variable 'innodb_instant_alter_column_allowed' can't be set to the value of '-1' 25select @@global.innodb_instant_alter_column_allowed; 26@@global.innodb_instant_alter_column_allowed 27never 28set global innodb_instant_alter_column_allowed=2; 29ERROR 42000: Variable 'innodb_instant_alter_column_allowed' can't be set to the value of '2' 30select @@global.innodb_instant_alter_column_allowed; 31@@global.innodb_instant_alter_column_allowed 32never 33set global innodb_instant_alter_column_allowed=1; 34select @@global.innodb_instant_alter_column_allowed; 35@@global.innodb_instant_alter_column_allowed 36add_last 37set global innodb_instant_alter_column_allowed=0; 38select @@global.innodb_instant_alter_column_allowed; 39@@global.innodb_instant_alter_column_allowed 40never 41set global innodb_instant_alter_column_allowed=default; 42select @@global.innodb_instant_alter_column_allowed; 43@@global.innodb_instant_alter_column_allowed 44add_last 45SET GLOBAL innodb_instant_alter_column_allowed = @start_global_value; 46