1054 - Unknown column 'pc.products_id' in 'on clause'

SELECT DISTINCT p.products_id, p.products_image, p.products_price, p.products_vpe, p.products_vpe_status, p.products_vpe_value, p.products_base_price_unit, p.products_base_price_value, p.products_tax_class_id, p.products_shipping, p.products_free_shipping, p.products_national_shipping_only, p.products_mode, p.products_date_available, p.products_variation, p.products_shippingtime, p.products_quantity, p.products_stock_check, p.products_fsk18, pd.products_name, pd.products_short_description, pd.products_link_text, pd.products_link_title, m.manufacturers_virtual, m.manufacturers_name, m.manufacturers_products_prefix, m.shipping_status_id, s.specials_new_products_price, p.products_startpage FROM products AS p INNER JOIN products_to_categories AS p2c ON p2c.products_id = p.products_id INNER JOIN categories AS c ON c.categories_id = p2c.categories_id INNER JOIN categories AS c2 ON (c2.categories_id = c.categories_id OR c.node_left BETWEEN c2.node_left AND c2.node_right) AND c2.categories_id = '2110' INNER JOIN products_description AS pd ON pd.products_id = p.products_id AND pd.language_id = '2' LEFT JOIN manufacturers AS m ON p.manufacturers_id = m.manufacturers_id LEFT JOIN specials AS s ON p.products_quantity > 0 AND s.products_id = IF(p.products_variation = '', p.products_id, pc.products_id) AND s.status = '1' WHERE p.products_status = '1' AND p.origin_products_id IS NULL AND p.products_id_parent IS NULL AND p.manufacturers_id = '50' ORDER BY p.products_startpage DESC, p.products_ordered ASC

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