SET @start_global_value = @@global.aria_pagecache_age_threshold;
select @@global.aria_pagecache_age_threshold;
@@global.aria_pagecache_age_threshold
300
select @@session.aria_pagecache_age_threshold;
ERROR HY000: Variable 'aria_pagecache_age_threshold' is a GLOBAL variable
show global variables like 'aria_pagecache_age_threshold';
Variable_name	Value
aria_pagecache_age_threshold	300
show session variables like 'aria_pagecache_age_threshold';
Variable_name	Value
aria_pagecache_age_threshold	300
select * from information_schema.global_variables where variable_name='aria_pagecache_age_threshold';
VARIABLE_NAME	VARIABLE_VALUE
ARIA_PAGECACHE_AGE_THRESHOLD	300
select * from information_schema.session_variables where variable_name='aria_pagecache_age_threshold';
VARIABLE_NAME	VARIABLE_VALUE
ARIA_PAGECACHE_AGE_THRESHOLD	300
set global aria_pagecache_age_threshold=200;
select @@global.aria_pagecache_age_threshold;
@@global.aria_pagecache_age_threshold
200
set session aria_pagecache_age_threshold=1;
ERROR HY000: Variable 'aria_pagecache_age_threshold' is a GLOBAL variable and should be set with SET GLOBAL
set global aria_pagecache_age_threshold=1.1;
ERROR 42000: Incorrect argument type to variable 'aria_pagecache_age_threshold'
set global aria_pagecache_age_threshold=1e1;
ERROR 42000: Incorrect argument type to variable 'aria_pagecache_age_threshold'
set global aria_pagecache_age_threshold="foo";
ERROR 42000: Incorrect argument type to variable 'aria_pagecache_age_threshold'
set global aria_pagecache_age_threshold=1;
Warnings:
Warning	1292	Truncated incorrect aria_pagecache_age_threshold value: '1'
select @@global.aria_pagecache_age_threshold;
@@global.aria_pagecache_age_threshold
100
set global aria_pagecache_age_threshold=@@global.aria_pagecache_age_threshold + 100 - 1;
Warnings:
Warning	1292	Truncated incorrect aria_pagecache_age_threshold value: '199'
select @@global.aria_pagecache_age_threshold;
@@global.aria_pagecache_age_threshold
100
set global aria_pagecache_age_threshold=@@global.aria_pagecache_age_threshold + 100;
select @@global.aria_pagecache_age_threshold;
@@global.aria_pagecache_age_threshold
200
set global aria_pagecache_age_threshold=cast(-1 as unsigned int);
Warnings:
Note	1105	Cast to unsigned converted negative integer to it's positive complement
Note	1105	Cast to unsigned converted negative integer to it's positive complement
Warning	1292	Truncated incorrect aria_pagecache_age_threshold value: '18446744073709551615'
select @@global.aria_pagecache_age_threshold;
@@global.aria_pagecache_age_threshold
18446744073709551600
SET @@global.aria_pagecache_age_threshold = @start_global_value;