select @@global.myisam_recover_options; @@global.myisam_recover_options OFF select @@session.myisam_recover_options; ERROR HY000: Variable 'myisam_recover_options' is a GLOBAL variable show global variables like 'myisam_recover_options'; Variable_name Value myisam_recover_options OFF show session variables like 'myisam_recover_options'; Variable_name Value myisam_recover_options OFF select * from information_schema.global_variables where variable_name='myisam_recover_options'; VARIABLE_NAME VARIABLE_VALUE MYISAM_RECOVER_OPTIONS OFF select * from information_schema.session_variables where variable_name='myisam_recover_options'; VARIABLE_NAME VARIABLE_VALUE MYISAM_RECOVER_OPTIONS OFF set global myisam_recover_options=1; ERROR HY000: Variable 'myisam_recover_options' is a read only variable set session myisam_recover_options=1; ERROR HY000: Variable 'myisam_recover_options' is a read only variable