1SET @start_value = @@global.general_log_file; 2SELECT @start_value; 3@start_value 4test.log 5'#---------------------FN_DYNVARS_004_01-------------------------#' 6SET @@global.general_log_file = DEFAULT; 7SET @a=concat(left(@@hostname, instr(concat(@@hostname, '.'), '.')-1), '.log'); 8SELECT RIGHT(@@global.general_log_file, length(@a)) = @a; 9RIGHT(@@global.general_log_file, length(@a)) = @a 101 11'#--------------------FN_DYNVARS_004_02------------------------#' 12SET @@global.general_log_file = mytest.log; 13ERROR 42000: Incorrect argument type to variable 'general_log_file' 14SET @@global.general_log_file = 12; 15ERROR 42000: Incorrect argument type to variable 'general_log_file' 16'#----------------------FN_DYNVARS_004_03------------------------#' 17SELECT @@global.general_log_file = VARIABLE_VALUE 18FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES 19WHERE VARIABLE_NAME='general_log_file'; 20@@global.general_log_file = VARIABLE_VALUE 211 22SET @@global.general_log_file= @start_value; 23