--source include/not_embedded.inc SET @start_global_value = @@global.sync_relay_log; SELECT @start_global_value; # # exists as global only # select @@global.sync_relay_log; --error ER_INCORRECT_GLOBAL_LOCAL_VAR select @@session.sync_relay_log; show global variables like 'sync_relay_log'; show session variables like 'sync_relay_log'; select * from information_schema.global_variables where variable_name='sync_relay_log'; select * from information_schema.session_variables where variable_name='sync_relay_log'; # # show that it's writable # set global sync_relay_log=1; select @@global.sync_relay_log; --error ER_GLOBAL_VARIABLE set session sync_relay_log=1; # # incorrect types # --error ER_WRONG_TYPE_FOR_VAR set global sync_relay_log=1.1; --error ER_WRONG_TYPE_FOR_VAR set global sync_relay_log=1e1; --error ER_WRONG_TYPE_FOR_VAR set global sync_relay_log="foo"; # # min/max values # set global sync_relay_log=0; select @@global.sync_relay_log; set global sync_relay_log=cast(-1 as unsigned int); select @@global.sync_relay_log; SET @@global.sync_relay_log = @start_global_value; SELECT @@global.sync_relay_log;