Sql request for product_attribute count is unstable

[tomiiq]

hello,

I have sql request for product attributes count, but server return 2 different results short time. Mostly returns 26000 but in some cases returns 8000 attributes. Can you give me advice about what is wrong on this sql request? I have created module for prestashop where I need this count and problem is only on one customer server propably.

SELECT COUNT(pa.id_product_attribute) FROM ps_product_attribute pa JOIN ps_product_attribute_shop pas ON (pas.id_product_attribute = pa.id_product_attribute AND pas.id_shop = 1) JOIN ps_product_shop ps ON (pa.id_product = ps.id_product AND ps.active = 1 AND ps.id_shop = 1) JOIN ps_stock_available sa ON (sa.id_product = pa.id_product AND sa.id_product_attribute = pa.id_product_attribute AND (sa.id_shop = 0 OR sa.id_shop = 1)) WHERE ps.id_shop = 1 AND sa.quantity > 0 AND ps.visibility = 'both' AND ps.active = 1