Counting # of rows in table which contain file_name - php

Question

I am trying to make a page which displays products added to a database.
I need to use 'foreach' to automatically display all products.
Im stuck with one part where I need to display the number of downloads of each product. The only way to do this is to count the number of rows which contain the file name of the product in the downloads table.
This is what I use so far, but its not working:
SELECT * FROM products, file_product, files, downloads WHERE products.id = file_product.product_id AND file_product.file_id = files.id AND files.file_name = downloads.file_name
These are my tables: [products, file_product, files, downloads]

Answer 1

It sounds to me like you're doing this the hard way. I might suggest you look at mysql's grouping functions, specifically GROUP BY. You won't have to loop over the query at all, just the results.
Something like
SELECT `file_name`, COUNT(*) AS `count` FROM `files` GROUP BY `file_name`;
The results should look something like this:
---------------------------
| file_name | count|
--------------------------|
| background-2.png | 2 |
| foo.png | 1 |
---------------------------
You can JOIN that with your file_product table if you need to limit it to only files for the current product, as what I wrote will give you all files for all products.
Example:
SELECT
f.`file_name`,
COUNT(*) AS `count`
FROM `files` f
JOIN `file_product` fp
ON fp.`file_id` = f.`id`
JOIN `product` p
ON fp.`product_id` = ?
JOIN `downloads` d
ON d.`file_name` = f.`file_name`
GROUP BY `file_name`;
? is where you put the product id for the current product.

Answer 2

You have to write :
SELECT `file_name'`, COUNT(*) AS `count` FROM table GROUP BY `count` ORDER BY `count` DESC;
Then, this command returns how many rows per table for each file_name group by descroissant order.
In order to implement whith PHP :
<?php
// connect to MySQL
$db = mysql_connect('localhost', 'login', 'password');
// select database
mysql_select_db('database_name',$db);
// SQL query
$sql = 'SELECT `file_name`, COUNT(*) AS `count` FROM table GROUP BY `count` ORDER BY `count` DESC;';
$req = mysql_query($sql) or die('Error SQL !<br>'.$sql.'<br>'.mysql_error());
// close mysql
mysql_close();
?>
I can't test it, so it's maybe false :/