1select @@global.aria_pagecache_file_hash_size; 2@@global.aria_pagecache_file_hash_size 3512 4select @@session.aria_pagecache_file_hash_size; 5ERROR HY000: Variable 'aria_pagecache_file_hash_size' is a GLOBAL variable 6show global variables like 'aria_pagecache_file_hash_size'; 7Variable_name Value 8aria_pagecache_file_hash_size 512 9show session variables like 'aria_pagecache_file_hash_size'; 10Variable_name Value 11aria_pagecache_file_hash_size 512 12select * from information_schema.global_variables where variable_name='aria_pagecache_file_hash_size'; 13VARIABLE_NAME VARIABLE_VALUE 14ARIA_PAGECACHE_FILE_HASH_SIZE 512 15select * from information_schema.session_variables where variable_name='aria_pagecache_file_hash_size'; 16VARIABLE_NAME VARIABLE_VALUE 17ARIA_PAGECACHE_FILE_HASH_SIZE 512 18set global aria_pagecache_file_hash_size=200; 19ERROR HY000: Variable 'aria_pagecache_file_hash_size' is a read only variable 20set session aria_pagecache_file_hash_size=200; 21ERROR HY000: Variable 'aria_pagecache_file_hash_size' is a read only variable 22