ms访问查询错误

Question

我正在将我的数据库从SQL Server转换为MS Access。

此查询在SQL Server中正常工作，但它在MS-Access中有语法错误。

那么这条SQL语句有什么问题？

select * 
from Students 
left join (select Lessons.StudentID, COUNT(*) as LessonsCount 
      from Lessons 
      group by Lessons.StudentID) as c on c.StudentID = Students.ID 
left join (select Tests.StudentID, count(*) as TestsCount 
      from Tests 
      group by Tests.StudentID) as dd on dd.StudentID = c.StudentID 

Answer 1

访问SQL需要括号多个连接。处理这个问题的自动防故障方法是在查询设计器中设置连接，并让Access添加它想要的括号。

可能出来找这样的事：

select * 
from (Students 
left join [select Lessons.StudentID, COUNT(*) as LessonsCount 
      from Lessons 
      group by Lessons.StudentID]. as c on c.StudentID = Students.ID) 
left join [select Tests.StudentID, count(*) as TestsCount 
      from Tests 
      group by Tests.StudentID]. as dd on dd.StudentID = c.StudentID 

与查询设计一个副作用是，它往往从子查询这种形式

(SELECT some_field FROM some_table) AS sub 

将此转换...

[SELECT some_field FROM some_table]. AS sub