List records in mysql using php

Answer 1

You will find the value in the $_POST[] array.

$result = mysql_query("SELECT * FROM students WHERE ADDRESS = '{$_POST["grup"]}'");

This approach can be dangerous though - you'll want to also sanitize your $_POST[] data against SQL injection attacks - of which there are plenty of tutorials available.

Answer 2

$_POST['grup'] will contain the value in the field when posted.

Then do something like:

$result = mysql_query(sprintf("SELECT * FROM students WHERE ADDRESS='%s'", mysql_real_escape_string($_POST['grup'], $con)));

If you dont escape the POST value with sprintf and mysql_real_escape_string you can be targeted by SQL injection attacks.

http://en.wikipedia.org/wiki/SQL_injection