Question

我有MySQL查询的问题，我有两个表 - 优惠和出价：

offers                       bids

id status                  id offer_id user_id
1  new                     1     1        1
2  new                     2     1        2
3  rejected                3     2        1    
4  accepted                4     4        4
5  new                     5     5        2
6  new                     6     6        3
7  new                     7     7        1

假设user_id = 2，我需要此user_id的所有商品（来自餐桌优惠），其中status =“new”，但没有这些商品的出价（没有商品1和商品5）

我尝试过“不存在”但没有太大成功。像：

SELECT distinct o.*
FROM offers o 
LEFT JOIN bids AS b 
ON o.id = b.offer_id
WHERE o.status = "new" AND (b.user_id!=2 
OR NOT EXISTS (SELECT * FROM  offers off WHERE b.offer_id = off.id))

类似（当没有其他用户出价相同时，我可以得到结果），但是我无法得到我需要的东西。

编辑：

在这种情况下作为输出我需要带ID的优惠：

2 6 7（提供3和4不是“新”以及用户已经出价的优惠1和5）

Answer 1

你不需要在这里加入。它非常简单

选择状态为new
排除user = 2出价

查询：

SELECT * FROM offers o
WHERE o.`status` = 'new' AND
    o.id NOT IN (SELECT offer_id from bids b WHERE b.user_id = 2)

Answer 2

this.users = [...this.users , ...this.usersnew];

Answer 3

这应该有效：

SELECT distinct o.*
FROM offers o
WHERE o.status = "new" AND
      o.id not in (select offer_id from bids where user_id = 2);

如果要显示所有用户，请尝试以下查询：

SELECT distinct o.*
    FROM offers o 
    Inner JOIN bids AS b 
    ON o.id = b.offer_id
    WHERE o.status = "new" AND              
Group by b.user_id
having o.id not in (select offer_id from bids b1 where b1.user_id = b.user_id);

其他表中没有外键的SQL查询

3 个答案: