dtrj21373 2015-08-31 13:53
浏览 87

如何在codeigniter 3中创建两个连接?

I have 3 Tables:

**Clients**
id | names 
1  | Paul
2  | Jack

**Course** 
id | names 
1  | Med 
2  | Nur 

**Class** 
class_id | clients_id  | course_id 
1        |   1         | 1
2        |   2         | 1
3        |   1         | 2 

**I want to show this:** 

**Result**
class_id |clients_names | courses_names
1        | Paul         | Med
2        | Jack         | Med 
3        | Paul         | Nur

How can i get this Result? I already know how to make one join, but this double join is driving me crazy.

Thks.

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2条回答 默认 最新

  • douhe5092 2015-08-31 14:01
    关注

    Try;

    select 
        c.class_id, cl.names clients_names, co.names courses_names
    from Class c
    join Clients cl on cl.id = c.clients_id
    join Course co on co.id = c.course_id 
    
    评论

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