<?php
	// Open the connection
                $con = mysql_connect("localhost","user","password")
                or die('No connection could be established: ' . mysql_error());
       // Select the database
                mysql_select_db("db", $con);
                
	//in our html file, there is an id submitted which we are using here
                $result = mysql_query("SELECT * from tablename where id = '".$_POST['chooseId']."'")
                or die ("MySQL-Error: " . mysql_error());  

	// Here we fill our data into an array
                while($row = mysql_fetch_array($result))
                {
	
	// "First"=>$row['First'] means you will be able to show the first row of your record by referencing 
		data.First later in your jQuery script
                    $data = array ("First"=>$row['First'],"Second"=>$row['Second']);
                    
	// We encode our array as JSON, as it is easier to process
                    $jsondata = json_encode($data);
                   
                }

	// Finally we return the data
                echo "$jsondata";
?>