1select @@global.innodb_sort_buffer_size; 2@@global.innodb_sort_buffer_size 31048576 4select @@session.innodb_sort_buffer_size; 5ERROR HY000: Variable 'innodb_sort_buffer_size' is a GLOBAL variable 6show global variables like 'innodb_sort_buffer_size'; 7Variable_name Value 8innodb_sort_buffer_size 1048576 9show session variables like 'innodb_sort_buffer_size'; 10Variable_name Value 11innodb_sort_buffer_size 1048576 12select * from information_schema.global_variables where variable_name='innodb_sort_buffer_size'; 13VARIABLE_NAME VARIABLE_VALUE 14INNODB_SORT_BUFFER_SIZE 1048576 15select * from information_schema.session_variables where variable_name='innodb_sort_buffer_size'; 16VARIABLE_NAME VARIABLE_VALUE 17INNODB_SORT_BUFFER_SIZE 1048576 18set global innodb_sort_buffer_size=1; 19ERROR HY000: Variable 'innodb_sort_buffer_size' is a read only variable 20set session innodb_sort_buffer_size=1; 21ERROR HY000: Variable 'innodb_sort_buffer_size' is a read only variable 22