Pb sous requete

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;

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;

SELECT
products_description.products_name
FROM
products_description
WHERE
products_description.products_id in ( SELECT distinct products_to_categories.products_id
FROM

products_to_categories
WHERE
products_to_categories.categories_id = 5)

pourqoui elle ne marche pas merci!