无法找到导致mysql语句错误的问题

Question

因此，对于我拥有的此特定mysql，我尝试将2个表连接在一起，然后在连接表的另一列中选择具有最大值的名称。 我怀疑问题是我将2条语句连接在一起。

select ds_name
from result 
where result.ds_sectionnumber = (select max(ds_sectionnumber) from result) 
from (select department.Dcode as ds_code, department.Dname as ds_name, section.Sectionnumber as ds_sectionnumber 
from department join section on department.Dcode = section.Dcode) as result;

Answer 1

您的查询应为：

select ds_name
  FROM (select department.Dcode as ds_code,
               department.Dname as ds_name, 
               section.Sectionnumber as ds_sectionnumber 
        FROM department 
        JOIN section on department.Dcode = section.Dcode) as result
  WHERE ds_sectionnumber = (
            select max(ds_sectionnumber) FROM 
                  (select department.Dcode as ds_code,
                     department.Dname as ds_name, 
                    section.Sectionnumber as ds_sectionnumber 
                       FROM department 
                       JOIN section 
                      ON department.Dcode = section.Dcode) as result);