How to show all product reference in sql manger?

[Wilfredcy]

SELECT 

a.`id_product`,
b.`name`,
pa.`reference`,
b.`link_rewrite` AS `url`,
a.`price` AS `price`,
sav.`quantity`,
m.`name` AS `Manufacturer`,
cl.`name` AS `name_category`,
tx.`name` AS `tax`

FROM `ps_product` a 
LEFT JOIN `ps_product_lang` b ON (b.`id_product` = a.`id_product`) 
LEFT JOIN `ps_stock_available` sav ON (sav.`id_product` = a.`id_product`) 
LEFT JOIN `ps_manufacturer` m ON (a.id_manufacturer = m.id_manufacturer)
LEFT JOIN `ps_product_shop` pshop ON (pshop.`id_product` = a.`id_product`)
LEFT JOIN `ps_category_lang` cl ON (pshop.`id_category_default` = cl.`id_category`) 
LEFT JOIN `ps_tax_rules_group` tx ON ( tx.`id_tax_rules_group` = a.`id_tax_rules_group`)
LEFT JOIN  `ps_product_attribute` pa ON (pa.`id_product` = a.`id_product`)

WHERE 1 ORDER BY a.`id_product` ASC        

I try to export product detail with SQL manager, but in the references column, only the product with combination got to show the reference code, but not the product with no combination. How can I show both of the references?

and another thing why is all the product are duplicated.

[Wilfredcy]

Anyone? Help!!!