sql - MySQL 计数语句错误 - 操作数应包含 1 列

Question

我正在尝试进行多次计数，每个人都在接受第一个子选择 (list1) 我收到一条错误消息“Operand should contain 1 column(s)”我猜它有与 AND 有关，但我不确定如何解决这个问题。

  Select Count(list0.ustatus) AS finished_count
       ,   (Select list1.ustatus, Count(*) 
              From listofupdates list1 
             Where list1.ustarted != '0000-00-00 00:00:00' 
               AND list1.ustatus != 1
           ) AS start_count
       ,   (Select Count(list2.udifficulty) 
              From listofupdates list2 
             Where  list2.udifficulty = 2
           )  AS recheck_count
       ,   (Select Count(list3.udifficulty) 
              From listofupdates list3 
              Where  list3.udifficulty = 4
           )  AS question_count 
     From listofupdates as list0 
    Where  list0.ustatus = 1 

Answer 1

我完全同意@Chad Birch 的观点

以下查询应该有效。

 Select Count(list0.ustatus) AS finished_count
       ,   (Select  Count(*) 
              From listofupdates list1 
             Where list1.ustarted != '0000-00-00 00:00:00' 
               AND list1.ustatus != 1
           ) AS start_count
       ,   (Select Count(list2.udifficulty) 
              From listofupdates list2 
             Where  list2.udifficulty = 2
           )  AS recheck_count
       ,   (Select Count(list3.udifficulty) 
              From listofupdates list3 
              Where  list3.udifficulty = 4
           )  AS question_count 
     From listofupdates as list0 
    Where  list0.ustatus = 1