SET @start_global_value = @@global.alter_algorithm;
SET GLOBAL alter_algorithm=1.1;
ERROR 42000: Incorrect argument type to variable 'alter_algorithm'
SET GLOBAL alter_algorithm=-1;
ERROR 42000: Variable 'alter_algorithm' can't be set to the value of '-1'
SET GLOBAL alter_algorithm=weird;
ERROR 42000: Variable 'alter_algorithm' can't be set to the value of 'weird'
SET GLOBAL alter_algorithm=4;
SELECT @@global.alter_algorithm;
@@global.alter_algorithm
INSTANT
SET GLOBAL alter_algorithm=3;
SELECT @@global.alter_algorithm;
@@global.alter_algorithm
NOCOPY
SET GLOBAL alter_algorithm=0;
SELECT @@global.alter_algorithm;
@@global.alter_algorithm
DEFAULT
SET GLOBAL alter_algorithm=1;
SELECT @@global.alter_algorithm;
@@global.alter_algorithm
COPY
SET GLOBAL alter_algorithm=2;
SELECT @@global.alter_algorithm;
@@global.alter_algorithm
INPLACE
SET GLOBAL alter_algorithm=5;
ERROR 42000: Variable 'alter_algorithm' can't be set to the value of '5'
SELECT @@global.alter_algorithm;
@@global.alter_algorithm
INPLACE
SET GLOBAL alter_algorithm=NOCOPY;
SET alter_algorithm=1.1;
ERROR 42000: Incorrect argument type to variable 'alter_algorithm'
SET alter_algorithm=-1;
ERROR 42000: Variable 'alter_algorithm' can't be set to the value of '-1'
SET alter_algorithm=weird;
ERROR 42000: Variable 'alter_algorithm' can't be set to the value of 'weird'
SET alter_algorithm=4;
SELECT @@alter_algorithm;
@@alter_algorithm
INSTANT
SET alter_algorithm=3;
SELECT @@alter_algorithm;
@@alter_algorithm
NOCOPY
SET alter_algorithm=0;
SELECT @@alter_algorithm;
@@alter_algorithm
DEFAULT
SET alter_algorithm=1;
SELECT @@alter_algorithm;
@@alter_algorithm
COPY
SET alter_algorithm=2;
SELECT @@alter_algorithm;
@@alter_algorithm
INPLACE
SET alter_algorithm=5;
ERROR 42000: Variable 'alter_algorithm' can't be set to the value of '5'
SELECT @@alter_algorithm;
@@alter_algorithm
INPLACE
SET SESSION alter_algorithm=INSTANT;
SHOW SESSION VARIABLES LIKE 'alter_algorithm';
Variable_name	Value
alter_algorithm	INSTANT
SET SESSION alter_algorithm=DEFAULT;
SHOW SESSION VARIABLES LIKE 'alter_algorithm';
Variable_name	Value
alter_algorithm	NOCOPY
SET SESSION alter_algorithm='DEFAULT';
SHOW SESSION VARIABLES LIKE 'alter_algorithm';
Variable_name	Value
alter_algorithm	DEFAULT
SET SESSION alter_algorithm=DEFAULT;
SHOW SESSION VARIABLES LIKE 'alter_algorithm';
Variable_name	Value
alter_algorithm	NOCOPY
SET GLOBAL alter_algorithm=DEFAULT;
SHOW SESSION VARIABLES LIKE 'alter_algorithm';
Variable_name	Value
alter_algorithm	NOCOPY
SET SESSION alter_algorithm=DEFAULT;
SHOW SESSION VARIABLES LIKE 'alter_algorithm';
Variable_name	Value
alter_algorithm	DEFAULT
SET GLOBAL alter_algorithm = @start_global_value;