Question

All i need is a simple explanation on how does this function work
I also attached a piece of php which I think is the one that retrieves the data from the database. Please correct me if I’m wrong

Cheers.

   function loadDatabaseRecords () 
{
// Mozilla/Safari
if (window.XMLHttpRequest) 
{
    xmlHttpReq = new XMLHttpRequest();
}
// IE
else if (window.ActiveXObject) 
{
    xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
}

alert ("To Server (Load Records):\n\najax-open-DB.php");

xmlHttpReq.open('GET', "ajax-open-DB.php", true);
xmlHttpReq.onreadystatechange = loadDatabaseRecordsCallback; 
xmlHttpReq.send(null);
}





<?php
  $link = mysql_connect ("ipaddress", "localhost", "password");
  mysql_select_db ("database1");

  $query = "SELECT * from addressbook";
  $result = mysql_query ($query);

  print "<table>";
  print "<tr>";
  print "<th>Firstname</th><th>Lastname</th><th>Address</th><th>Telephone</th>";
  print "</tr>";
  for ($i = 0; $i < mysql_num_rows ($result); $i ++)
  {        
    $row = mysql_fetch_object ($result);
    print "<tr>";
    print "<td>$row->firstname</td>";
    print "<td>$row->lastname</td>";
    print "<td>$row->address</td>";
    print "<td>$row->telephone</td>";
    print "</tr>";
  }
  print "</table>";
  mysql_close ($link);
?>

Answer 1

mysql_connect connects to MySQL using the hostname (ipaddress), username (localhost) and password (password). select_db then chooses the database (database1).

mysql_query queries the database for all records (select *) in a certain table (addressbook), through the connection you just made. Generally, people also reference the connection, as in mysql_query ($query, $link)

fetch_object fetches the next row from that query, one at a time, and php formats the results with td/tr, etc.