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