podwójne wyniki Opcje

[krzyszbi]

witam
mam takie otozapytanie

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SELECT DISTINCT (
p.products_id
), d.products_description
FROM `products` AS p, `products_to_categories` AS c, `products_description` AS d
WHERE p.products_id = c.products_id = d.products_id AND c.categories_id =4
LIMIT 0, 30
[SQL] pobierz, plaintext 

i cos takiego zwraca mi podwójne wyniki ( jak nie ma w zapytaniu d.products_description to jest ok a jak sie doda cos więcej to mam nawet czasami potrójne wyniki)
co tu mam źle
struktóry tabel

[SQL] pobierz, plaintext 
CREATE TABLE `products_to_categories` (
`products_id` int(11) NOT NULL DEFAULT '0',
`categories_id` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY  (`products_id`,`categories_id`)
) TYPE=MyISAM
[SQL] pobierz, plaintext 

[SQL] pobierz, plaintext 
CREATE TABLE `products_description` (
`products_id` int(11) NOT NULL AUTO_INCREMENT,
`language_id` int(11) NOT NULL DEFAULT '1',
`products_name` varchar(64) NOT NULL DEFAULT '',
`products_description` text,
`products_url` varchar(255) DEFAULT NULL,
`products_viewed` int(5) DEFAULT '0',
PRIMARY KEY  (`products_id`,`language_id`),
KEY `products_name` (`products_name`)
) TYPE=MyISAM
[SQL] pobierz, plaintext 

[SQL] pobierz, plaintext 
CREATE TABLE `products` (
`products_id` int(11) NOT NULL AUTO_INCREMENT,
`products_quantity` int(4) NOT NULL DEFAULT '0',
`products_model` varchar(12) DEFAULT NULL,
`products_image` varchar(64) DEFAULT NULL,
`products_price` decimal(15,4) NOT NULL DEFAULT '0.0000',
`products_date_added` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
`products_last_modified` datetime DEFAULT NULL,
`products_date_available` datetime DEFAULT NULL,
`products_weight` decimal(5,2) NOT NULL DEFAULT '0.00',
`products_status` tinyint(1) NOT NULL DEFAULT '0',
`products_tax_class_id` int(11) NOT NULL DEFAULT '0',
`manufacturers_id` int(11) DEFAULT NULL,
`products_ordered` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY  (`products_id`),
KEY `idx_products_date_added` (`products_date_added`)
) TYPE=MyISAM
[SQL] pobierz, plaintext 

tabele takie są zawarte w osComerce - ( darmowy sklep internetowy który przerabiam ) i nie zabardzo mi to wychodzi jak widac od strony MySql-a z php sobie radze