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Home Backend Development PHP Tutorial 求一个sql语句(有点难,求高手)

求一个sql语句(有点难,求高手)

Jun 23, 2016 pm 02:23 PM

本帖最后由 dz215136304 于 2013-07-28 11:58:31 编辑


id pid title
1   0   标题1
2   0   标题2
3   2   标题3
4   2   标题4
5   2   标题5
6   5   标题6

需求 将表里的数据都查出来 并且如果pid等于别的数据id的话 id那条数据自动生成个字段,字段的数据是pid连接起来的且通过,分割 ,效果如下

id pid title   pidss
1   0   标题1  
2   0   标题2  3,4,5
3   2   标题3
4   2   标题4
5   2   标题5  6
6   5   标题6

回复讨论(解决方案)

这没有什么复杂的

select a.*, pidss from tbl_name a left join  (select *, group_concat(id) as pidss from tbl_name where pid>0 group by pid) t on a.id=t.pid
Copy after login

不过当层次深的时候就不一定是你期望的了

过来看一看。

二楼的正确,用做链接保证不丢失数据,用group_cancat函数将单值属性连接起来编程多值属性。

group_cancat函数可以解决

group_concat

学习了,不错。

学习了,不错,本来我对这个还不太了解呢,这次了解了

学习了,不错学习了,不错

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