我有一个用户表和页表，这两个表与桥接表用户权限之间存在多对多关系。我想要获取所有页面名称，并且仅获取那些标记为分配给该用户的页面。
想要一些这样的想法
+---------+----------------------------------+
| user_id | page_name | Assigned|
+---------+----------------------------------+
| 1 | Add Project | 0 |
| 1 | Department | 0 |
| 1 | Category | 1 |
| 1 | Item | 0 |
| 1 | Units | 1 |
| 1 | Stock In | 0 |
| 1 | Stock Card Report | 1 |
+---------+------------------------+---------|
现在我的查询是这样的；
Select up.user_id, p.page_name FROM user_privileges up, pages p where p.page_id = up.page_id and up.user_id = 1;
它返回这个；
+---------+------------------------+
| user_id | page_name |
+---------+------------------------+
| 1 | Add Project |
| 1 | Department |
| 1 | Category |
| 1 | Item |
| 1 | Units |
| 1 | Stock In |
| 1 | Stock Card Report |
+---------+------------------------+
方案是这样的； 表 - 用户
+---------+-----------+
| user_id | user_name |
+---------+-----------+
| 4 | saif |
| 1 | admin |
| 5 | taqi |
| 2 | rashid |
+---------+-----------+
表格 - 页面
+---------+---------------+
| page_id | page_name |
+---------+---------------+
| 2 | Page 1 |
| 3 | Page 2 |
| 5 | Page 3 |
| 6 | Page 4 |
| 7 | Page 5 |
| 8 | Page 6 |
| 9 | Page 7 |
| 10 | Page 8 |
| 11 | Page 9 |
| 13 | Page 10 |
| 14 | Page 11 |
| 15 | Page 12 |
| 16 | Page 13 |
| 18 | Page 14 |
| 19 | Page 15 |
| 20 | Page 16 |
+---------+---------------+
和表 user_privalges 仅适用于 user_id = 1。
+--------------------+---------+---------+
| user_privileges_id | user_id | page_id |
+--------------------+---------+---------+
| 1 | 1 | 2 |
| 2 | 1 | 3 |
| 3 | 1 | 5 |
| 4 | 1 | 6 |
| 5 | 1 | 7 |
| 6 | 1 | 8 |
| 7 | 1 | 9 |
| 8 | 1 | 10 |
| 9 | 1 | 11 |
| 10 | 1 | 13 |
| 11 | 1 | 14 |
| 12 | 1 | 15 |
| 13 | 1 | 16 |
| 14 | 1 | 18 |
| 15 | 1 | 19 |
| 16 | 1 | 20 |
+--------------------+---------+---------+
最佳答案
Select up.user_id, p.page_name FROM user_privileges up, pages p where p.page_id = up.page_id and up.user_id = 1 AND up.Assigned=1;
“我想要获取所有页面名称，并且仅获取那些标记为分配给该用户的页面。”因此，在编辑时，您应该尝试使用 case 语句进行类似的操作
SELECT up.user_id, p.page_name,
CASE
WHEN up.page_id=p.page_id THEN '1'
ELSE '0'
END AS Assigned
FROM pages p left join user_privileges up
ON p.page_id = up.page_id
WHERE up.user_id = 1;
关于php - MySQL在一个查询中从表中获取相关和不相关的记录，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/31849583/