Databases

[hargi]

Just revisiting an old project I did in a bit of a rush for our department.
But now I want to refine it and to learn more PHP/MySql along the way.

Basically its one big Database with one table in with no normalization going on at all? So there is a list of usernames, workplaces, that gets repeated etc.

How difficult is it to split it up once data has been entered? would i be best statring from scratch.

Also is there a way of using php or MySql to filter the results. so using something like

<?php require_once('Connections/conn.php'); 
// set up query for table data
mysql_select_db($database_conn, $conn);
$query = sprintf("SELECT Username FROM Entries");
$result = mysql_query($query);
$resultarray = array();
while($row=mysql_fetch_assoc($result)) {array_push($resultarray, $row);} 
$resultarray = array_unique($resultarray);



?>

Cheers