查询将返回唯一1的结果,请大家帮忙SQL查询只返回1个结果
select
p.products_id, pd.products_name
from
products_description pd,
products_to_categories p2c,
products p
where
EXISTS (SELECT p2pef.products_id
FROM products_to_products_extra_fields p2pef
WHERE p2pef.products_extra_fields_id = '78'
and p2pef.products_extra_fields_value = 'tak'
and p.products_id = p2pef.products_id)
and
EXISTS (SELECT p2pef.products_id
FROM products_to_products_extra_fields p2pef
WHERE p2pef.products_extra_fields_id = '94'
and p2pef.products_extra_fields_value = 'tak'
and p.products_id = p2pef.products_id)
and p.products_status = '1'
and p.products_id = pd.products_id
and p.products_id = p2c.products_id
and pd.language_id = '4'
and p2c.categories_id = '26'
group by p.products_id
你认为怎么样使用EXISTS此查询?
您可能有另一种想法来显示来自products_to_products_extra_fields表的其他字段满足多个条件的产品表中的产品。
表模式:
产品(4行)
_________________________
products_id
_________________________
1
2
3
4
products_to_products_extra_fields(8行)
___________________________________________________________________
products_id products_extra_fields_id products_extra_fields_value
___________________________________________________________________
1 94 tak
1 78 tak
2 94 tak
2 78 tak
3 94 tak
3 78 tak
4 94 nie
4 78 tak
有效的查询应该返回(3行)
_______________
products_id
_______________
1
2
3
'EXISTS'部分似乎没问题。问题可能是您的其他过滤器只选择了一个'product_id' –
的确,所有* product_ids *都不带'EXISTS'子句? – Parfait
嗨。 “满足几个条件”是什么意思?您似乎对输入“条件”的某种表示形式和输出查询感兴趣,但您没有足够详细地解释我们可以知道什么是正确的答案。请同时阅读[mcve]并采取行动。事实上,你的问题到底是什么? – philipxy