我有下表
---------------------------
|ID |Image | link |
|01 | | 02 |
|02 |steve.jpg | |
|03 |eric.jpg | |
----------------------------
链接字段存储ID,因此我可以设置两行之间的关系。
ID 01的链接字段设置为02.所以我希望ID 01使用在该字段中设置了ID的图像,所以它将是steve.jpg。
如何获取所有行,以便设置了链接字段的行以该图像结束?
答案 0 :(得分:2)
您可以使用自联接来显示链接ID的图像名称
select t.*,t1.Image as link_image
from t
left join t t1 on(t.link = t1.ID)
答案 1 :(得分:0)
SELECT a.id, b.image, a.link
FROM YourTable AS a
JOIN YourTable AS b ON a.link = b.id
UNION
SELECT id, image, link
FROM YourTable
WHERE link IS NULL
答案 2 :(得分:-1)
这样的事情:
(SELECT ID, Image from mytable WHERE link = '' )
UNION ALL
(SELECT m1.ID as ID, m2.Image as Image
FROM mytable AS m1 INNER JOIN mytable AS m2 ON ( m1.link=m2.ID )
)