Question

如何实现将一个字段里的数据挑出来分别显示的sql语句

例如：我的表结构是这样的，但是在页面上的绑定是省、市、县分别列出来的要怎样实现？





Answer 1

select t.省份,t.城市,p.shixian as 地区
from(select a.省份,b.shixian as 城市,b.cid
from (select shixian as 省份,cid from tb where id=0) a
left join tb as b on a.cid=b.id
) t
left join tb as p on t.cid=p.id
;

追问

为什么我点sql窗格里写的sql语句再点执行的时候会改变我写的sql语句内容？
譬如：我点sql窗格输入sql语句select * from table 点击执行的时候为什么会变成
select id,name,sex,birthday from table????

Answer 2

SELECT m.shixian, n.shixian AS Expr1, x.shixian AS Expr2
FROM (SELECT ID, CID, shixian
FROM (SELECT ID, CID, shixian
FROM chengshi
WHERE (CID = 0)) AS derivedtbl_1) AS m CROSS JOIN
(SELECT ID, CID, shixian
FROM chengshi AS chengshi_2
WHERE (CID = 1)) AS n CROSS JOIN
(SELECT ID, CID, shixian
FROM chengshi AS chengshi_1
WHERE (CID <> 0) AND (CID <> 1)) AS x