values('" . $username . "','" . $password . "','" . $time . "','" . $ip . "')";
values ("$username","$password","$time","$ip")Isn't this possible?
Because you need to correspond to the data type of each field in the database, if the string is not enclosed in quotation marks, an error will be reported
Because you need to correspond to the data type of each field in the database, if the string is not enclosed in quotation marks, an error will be reported