How would I go about taking all of the values in a table and adding them together?

(as in, there are 15 entries, how would I add them all up so that I can divide them and get the mean?)

if you want the average of all entries, use SQL like this:

select avg(col_name)
from table

I tired several variations of that and none worked.

How else can I go about this?

Please post your code, using the avg() function is the easiest way to do it.

PHP Code:

function get_rating($id) {
    global $host,$user,$pass,$db;
    
    $link = mysql_connect($host,$user,$pass);
    mysql_select_db($db);
    
    $query_c = " SELECT avg(`rating`),`n_id` FROM `news_rating` WHERE n_id = $id ";
    $result_c = mysql_query($query_c);
    
    $num_rows = mysql_num_rows($result_c);
    if($num_rows == "0") {
        $rating = "N/A";
    } else {    
        while($row = mysql_fetch_array($result_c, MYSQL_ASSOC)) {
            $rating = $row['rating'];
        }
    }
    
    mysql_free_result($result_c);
    mysql_close($link);
        
    return $rating;
} 


I could be using it wrong... I don't know.

use an alias for the field name

select avg('rating') as rating_alias from ...

Alright, I got it to work.

Now, this is going to sound newbish, but I can't remember (for the life of me) how to make a string display only the first 3 characters (there are 5 in the average). How do I do this again?

substr()