ORDER BY CASE不起作用？

Question

嗨我有DB2中正在工作的SQL語句。

select distinct 'IN' as STATUS, 
    (select count(*) from table.......) 
from table 

UNION ALL 

select distinct 'OUT', 
    (select count(*) from table.......) 
from table 

UNION ALL 

select distinct 'FINISHED', 
    (select count(*) from table.......) 
from table 

order by status 

但是，如果我的最後一行改爲

order by 
case STATUS 
when 'IN' then 1 
when 'OUT' then 2 
when 'FINISHED' then 3 
end 

我的查詢不起作用。 有人可以告訴我如何解決這個問題嗎？ 感謝

Answer 1

嘗試包裹UNION到上派生表和訂單時，你也能說出這這應該工作：

select * 
from ( 
    .... here goes your statement ... 
) t 
order by 
    case STATUS 
     when 'IN' then 1 
     when 'OUT' then 2 
     when 'FINISHED' then 3 
    end 

Answer 2

你好嘗試，如果我沒有記錯

order by 
    case 
     when STATUS='IN' then 1 
     when STATUS='OUT' then 2 
     when STATUS='FINISHED' then 3 
    end 

整理 年底爲FIELD_NAME

Answer 3

你總是可以將排序＃添加到狀態：

select distinct '1-IN' as STATUS, 
    (select count(*) from table.......) 
from table 

UNION ALL 

select distinct '2-OUT', 
    (select count(*) from table.......) 
from table 

UNION ALL 

select distinct '3-FINISHED', 
    (select count(*) from table.......) 
from table 

order by status