问题描述
MID-名称-PID
2 ---- A ----- 0
3 ---- M ----- 0
4 ---- N ----- 0
11 --- B ----- 2
12 --- C ----- 2
13 --- D ----- 3
14 --- E ----- 2
31 --- Z ---- 11
32 --- Y ---- 12
33 --- X ---- 12
34 --- W ---- 13
35 --- V ---- 14
上面是表结构.
我想编写一个查询(条件将为PID = 2)，将从中获取以下值
11
12
14
31
32
33
35
有人可以帮我写这个查询吗?
在此先感谢.
MID -- Name-- PID
2 ---- A ----- 0
3 ---- M ----- 0
4 ---- N ----- 0
11 --- B ----- 2
12 --- C ----- 2
13 --- D ----- 3
14 --- E ----- 2
31 --- Z ---- 11
32 --- Y ---- 12
33 --- X ---- 12
34 --- W ---- 13
35 --- V ---- 14
Above is the table structure.
I want to write a single query (where condition will be PID=2) from which this following value will be fetched
11
12
14
31
32
33
35
Can anyone help me to write this query?
Thanks in advance.
推荐答案
select Mid from urtable where pid=2
查询什么问题.它会给你同样的结果.如果要编写自连接查询，请使用解决方案1.
what problem in query. it will give you same result. no need of selfjoin if you want to write self join query use solution 1.
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