错误：未知列＆＃39;状态＆＃39;在＆＃39;字段列表＆＃39;

Question

SELECT item_number, item_name, description, status, active_date, inactive_date, creation_date, creation_by, last_updated_date, last_updated_by, 
(CASE WHEN inactive_date IS NULL THEN 
    CASE WHEN active_date <= curdate() THEN 'ACTIVE' ELSE 'FUTURE ACTIVE' END
 ELSE  
     CASE WHEN active_date = inactive_date THEN 'INACTIVE'
          WHEN active_date <= curdate() AND inactive_date > curdate() THEN 'ACTIVE'
          WHEN active_date >  curdate() AND inactive_date > curdate() THEN 'FUTURE ACTIVE' 
     ELSE 'INACTIVE' END 
 END) as status

请帮帮我。我是mysql的新手。

Answer 1

在您的SELECT中，您已包含status：

SELECT item_number, item_name, description, status

由于您将status定义为AS作为新列，因此我怀疑您的表本身没有status列。移除status并将该行转为

SELECT item_number, item_name, description, active_date, inactive_date, creation_date, creation_by, last_updated_date, last_updated_by, 

Answer 2

从select移除状态如果是case

的结果，则不需要它

SELECT item_number, item_name, description, active_date, inactive_date, creation_date, creation_by, last_updated_date, last_updated_by, 
(CASE WHEN inactive_date IS NULL THEN 
    CASE WHEN active_date <= curdate() THEN 'ACTIVE' ELSE 'FUTURE ACTIVE' END
 ELSE  
     CASE WHEN active_date = inactive_date THEN 'INACTIVE'
          WHEN active_date <= curdate() AND inactive_date > curdate() THEN 'ACTIVE'
          WHEN active_date >  curdate() AND inactive_date > curdate() THEN 'FUTURE ACTIVE' 
     ELSE 'INACTIVE' END 
 END) as Status

还缺少from课程。