联合中的SQL查询变量+ COUNT（）

Question

我需要帮助我需要

的SQL查询

 SELECT MachineID from TABLE1

然后

Count(Passfail) from TABLE2 WHERE MachineID= *MACHINEID

先前

from the SELECT语句到单个表中

Answer 1

你几乎把它写在那里。你需要阅读一些关于连接和sql group by的信息：

select T1.MachineId, count(T2.Passfail) from
Table1 T1 inner join Table2 T2 on T1.MachineId = T2.Machine Id
group by T1.MachineId

编辑： 对于根据PassFail值的单独计数，我使用：

select T1.MachineId, 
sum(case when T2.PassFail='pass' then 1 else 0 end) as 'pass',
sum(case when T2.PassFail='fail' then 1 else 0 end) as 'fail'
from Table1 T1 inner join 
Table2 T2 on T1.MachineId = T2.machineId 
group by T1.machineId