Question

我有以下SQL：

SELECT id FROM order o 
INNER JOIN order_payment p ON p.parent_id=o.entity_id 
WHERE o.state='new' 
AND o.created_at BETWEEN '2013-05-14' 
AND '2013-10-11 00:19:09' 
AND p.method IN ('paymethod_a', 'paymethod_b', 'paymethod_c') 
--AND o.id NOT IN (SELECT id FROM order o 
--INNER JOIN payment_method pm ON pm.order_id=o.id 
--WHERE o.created_at BETWEEN '2013-05-14' AND '2013-10-11 00:19:09')**

在评论部分，我不想获得表support_method.order_id（外键）上匹配的任何id。但是现在，系统更新改变了一些事情：现在我希望在注释区域得到相同的结果，PLUS：如果payment_method寄存器的'status = 0'列，我也必须得到那个id，如果订单那就没关系。 id在payment_method.order_id（外键）上。

我厌倦了SQL，任何人都可以帮助我吗？谢谢！

Answer 1

通常，NOT IN（子选择查询）的性能很差。相反，如果另一个表为NULL（表示不存在），则执行LEFT-JOIN并接受记录要好得多。如果您希望包含OTHER特殊条件，这也有助于您的条件。类似的东西：

SELECT 
      o.id 
   FROM 
      order o 
         JOIN order_payment op 
            ON o.entity_id = op.parent_id
           AND op.method in ('paymethod_a', 'paymethod_b', 'paymethod_c') 
         LEFT JOIN payment_method pm
            on o.id = pm.order_id
   where
          o.state='new' 
      AND o.created_at BETWEEN '2013-05-14' AND '2013-10-11 00:19:09' 
      AND ( pm.order_id IS NULL
           OR pm.status = 0 )

Answer 2

考虑到您要加入3个不同的表并包含状态0

SELECT id FROM order o 
INNER JOIN order_payment p ON p.parent_id=o.entity_id 
INNER JOIN payment_method t3 ON t3.order_ID = o.orderID
WHERE o.state='new' 
AND o.created_at BETWEEN '2013-05-14' 
AND '2013-10-11 00:19:09' 
--query modified,if there are only one parameters,Function 'IN' is not supported
AND p.method = 'payment_method'

--you never exclude status = 0 in payment_method table, so nothing is needed to do at all

SQL选择不在另一个表上的ID，除非该寄存器具有某些列数据

2 个答案: