[英]Multiple join on same table
My Schema is 我的架构是
CREATE TABLE IF NOT EXISTS `account` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(120) NOT NULL,
PRIMARY KEY (`id`)
);
CREATE TABLE IF NOT EXISTS `reseller_did` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`phone` int(11) NOT NULL,
`superadmin_id` int(11) NOT NULL DEFAULT '0',
`reseller_id` int(11) NOT NULL DEFAULT '0',
`admin_id` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`),
FOREIGN KEY (`superadmin_id`) REFERENCES account(`id`),
FOREIGN KEY (`reseller_id`) REFERENCES account(`id`),
FOREIGN KEY (`admin_id`) REFERENCES account(`id`)
)
I want to find the phone with their superadmin, reseller, admin name. 我想找到带有他们的超级管理员,经销商和管理员名称的电话。 The problem is that I cant join multiple times on the same id. 问题是我不能在同一个ID上多次加入。 The query I have tried 我尝试过的查询
select phone,superadmin_id,reseller_id, admin_id, name from reseller_did join
account on account.id=reseller_did.admin_id
The above query display the admin name by joining on admin_id but how to get superadmin name and reseller name of the same phone? 上面的查询通过加入admin_id来显示管理员名称,但是如何获取同一手机的超级管理员名称和经销商名称?
EDIT: Sample Input 编辑:样本输入
account table 帐户表
id name
3 SuperAdmin1
9 Reseller1
10 Admin1
reseller_did reseller_did
id phone superadmin_id reseller_id admin_id
1 9090909090 3 9 10
Sample output 样品输出
phone superadmin reseller admin
9090909090 SuperAdmin1 Reseller1 Admin1
Try this;) 尝试这个;)
select r.phone, a.name as admin, re.name reseller, s.name as superadmin
from reseller_did r
join account a on a.id = r.admin_id
join account s on s.id = r.superadmin_id
join account re on re.id = r.reseller_id
Or 要么
SELECT r.phone,
MAX(CASE WHEN a.id = r.admin_id THEN a.name END) as admin,
MAX(CASE WHEN a.id = r.reseller_id THEN a.name END) as reseller,
MAX(CASE WHEN a.id = r.superadmin_id THEN a.name END) as superadmin
FROM reseller_did r
INNER JOIN account a
ON a.id IN (r.admin_id, r.superadmin_id, r.reseller_id)
GROUP BY r.phone
This sql should thank to @sagi in this question Get multiple values from another table by different relations . 这个sql应该感谢@sagi在这个问题上通过不同的关系从另一个表中获取多个值 。
Hope this works 希望这行得通
select
rd.phone as Phone ,
a.name as Superadmin,
a1.name as Reseller,
account.name as Admin
from
reseller_did rd
join
account ON account.id = rd.admin_id
join
account a ON a.id = rd.superadmin_id
join
account a1 ON a1.id = rd.reseller_id
You can make three aliases of account
table and INNER JOIN these with reseller_did
table 您可以使用reseller_did
表创建account
表和INNER JOIN这三个别名
SELECT
R.id,
R.phone,
A1.name AS superadmin,
A2.name AS reseller,
A3.name AS admin
FROM reseller_did R
INNER JOIN account A1 ON R.superadmin_id = A1.id
INNER JOIN account A2 ON R.reseller_id = A2.id
INNER JOIN account A3 ON R.admin_id = A3.id ;
Alternative way: 替代方式:
You can use the following query to get the same result if you don't want to adopt INNER JOIN. 如果您不想采用INNER JOIN,则可以使用以下查询获得相同的结果。
SELECT
R.phone,
(SELECT name FROM account WHERE id = R.superadmin_id) AS SuperAdmin,
(SELECT name FROM account WHERE id = R.reseller_id) AS Reseller,
(SELECT name FROM account WHERE id = R.admin_id) AS Admin
FROM reseller_did R;
Caution: You are storing phone number in INT
datatype. 警告:您将电话号码存储为INT
数据类型。 You shouldn't use INT
for storing phone number. 您不应该使用INT
来存储电话号码。 Instead you should use VARCHAR
. 相反,您应该使用VARCHAR
。
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