php+mysqli_real_escape_string do not work for email id, what could be reason? mysql table shows record for userid and password but do not show record of emailid. Following are my code, obtained from w3school php example <?php$link = mysqli_connect("hostname", "user", "password", "databasel");/* check connection */if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit();}mysqli_select_db($link,"spinall"); $username = mysqli_real_escape_string($link, $username); $password = mysqli_real_escape_string($link, $password); $emailid = mysqli_real_escape_string($link, $emailid);$sql="INSERT INTO job_newuser (username,password,emailid)VALUES('$_POST[username]','$_POST[password]','$_POST[emailid]')";if (!mysqli_query($link,$sql)) { die('Error: ' . mysqli_error($con)); }echo "1 record added";mysqli_close($link); ?>i am not able to understand what could be mistake? can any body tell me