我有下表:

Technician
Tech_ID,First_Name,Last_Name

 RT_QUEUE_Delta
 Tech_ID, RT_Complete` (references a `Tech_ID` in `Technician`).


我需要从RT_Queue_Delta其中的RT_Completed = ??行中获取数据,但是在我的输出中,我需要具有与First_NameLast_nam相关的Tech_idRT_Completed e。

我可以匹配一个,但我不知道如何匹配两个。我试过了:

select RTTech.First_Name as RT_First_Name,
       RTTech.Last_Name as RT_Last_Name
from Technician as RTTech
         Join RT_Queue_Delta as RT
         on RT.RT_Completed = RTTech.Tech_ID

最佳答案

您可以多次加入Technician表:

select d.tech_id, t.first_name, t.last_name,
       d.rt_completed as completed_id,
       t2.first_name as completed_first_name,
       t2.last_name as completed_last_name
from RT_QUEUE_Delta d
    join Technician t on d.tech_id = t.tech_id
    join Technician t2 on d.RT_Completed = t2.tech_id

关于mysql - 同一张表上的多个联接,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/30203810/

10-10 06:01