progress bar with mysql query with php

Question

i am trying to update a progress bar with the iteration of a mysql query, and i can't understand how i can update the progress bar, and how i can found what number of row i have fetched, for example:

$query = 'SELECT tvshows.genres, tvshows.id_show FROM tvshows where tvshows.genres is not NULL';
$result = mysql_query($query);

$num_rows = mysql_num_rows($result);
echo $num_rows;

this: echo $num_rows; is the number of rows i have fetched, and then in this way i iterate the result:

while ($db_row = mysql_fetch_assoc($result)) 
{
    //Do seomthing with the row

}

but how i can know in what row i fetch to update then the progress bar? and anyone knows a good tutorial or sample code to do a progress bar? i have found this: http://w3shaman.com/article/php-progress-bar-script

but that example require these:

 for($i=1; $i<=$total; $i++){
// Calculate the percentation
$percent = intval($i/$total * 100)."%";

and i doesn't know how make it with the result of the php query, anyone can help me?

Answer 1

As mentioned in the comments, it should be an extemely slow query if you should have to use a progress bar.

If it is, you could just add a simple counter to your loop:

$i = 0;
while ($db_row = mysql_fetch_assoc($result)) 
{
    $i++;
    $percent = intval($i/$num_rows * 100)."%";

    //Do seomthing with the row

}

And then do as mentioned in the article.