SET @start_global_value = @@global.innodb_instant_alter_column_allowed;
SET GLOBAL innodb_instant_alter_column_allowed=never;
select @@session.innodb_instant_alter_column_allowed;
ERROR HY000: Variable 'innodb_instant_alter_column_allowed' is a GLOBAL variable
show global variables like 'innodb_instant_alter_column_allowed';
Variable_name	Value
innodb_instant_alter_column_allowed	never
show session variables like 'innodb_instant_alter_column_allowed';
Variable_name	Value
innodb_instant_alter_column_allowed	never
SELECT * FROM information_schema.global_variables
WHERE variable_name='innodb_instant_alter_column_allowed';
VARIABLE_NAME	VARIABLE_VALUE
INNODB_INSTANT_ALTER_COLUMN_ALLOWED	never
SELECT * FROM information_schema.session_variables
WHERE variable_name='innodb_instant_alter_column_allowed';
VARIABLE_NAME	VARIABLE_VALUE
INNODB_INSTANT_ALTER_COLUMN_ALLOWED	never
set global innodb_instant_alter_column_allowed=no;
ERROR 42000: Variable 'innodb_instant_alter_column_allowed' can't be set to the value of 'no'
set global innodb_instant_alter_column_allowed=1.1;
ERROR 42000: Incorrect argument type to variable 'innodb_instant_alter_column_allowed'
set global innodb_instant_alter_column_allowed=-1;
ERROR 42000: Variable 'innodb_instant_alter_column_allowed' can't be set to the value of '-1'
select @@global.innodb_instant_alter_column_allowed;
@@global.innodb_instant_alter_column_allowed
never
set global innodb_instant_alter_column_allowed=3;
ERROR 42000: Variable 'innodb_instant_alter_column_allowed' can't be set to the value of '3'
select @@global.innodb_instant_alter_column_allowed;
@@global.innodb_instant_alter_column_allowed
never
set global innodb_instant_alter_column_allowed=2;
select @@global.innodb_instant_alter_column_allowed;
@@global.innodb_instant_alter_column_allowed
add_drop_reorder
set global innodb_instant_alter_column_allowed=1;
select @@global.innodb_instant_alter_column_allowed;
@@global.innodb_instant_alter_column_allowed
add_last
set global innodb_instant_alter_column_allowed=0;
select @@global.innodb_instant_alter_column_allowed;
@@global.innodb_instant_alter_column_allowed
never
set global innodb_instant_alter_column_allowed=default;
select @@global.innodb_instant_alter_column_allowed;
@@global.innodb_instant_alter_column_allowed
add_drop_reorder
SET GLOBAL innodb_instant_alter_column_allowed = @start_global_value;
