带或条件的Mysql案例

Question

如何在mysql查询中编写一个案例,该案例检查特定列的null或0

CREATE TABLE tblConfirmationStatus (Confirm_Status TINY INT)

INSERT INTO tblConfirmationStatus 
Confirm_Status
VALUES
(1),
(0),
(1),
({null}),
(0),
(1),
({null})

要求的输出

ConfirmStatus

   Confirmed
   Not Confirmed
   Confirmed
   Not Confirmed
   Not Confirmed
   Confirmed
   Not Confirmed

0或Null - 未确认,1 - 确认

SELECT CASE Confirm_Status 
            WHEN NULL OR 0 THEN 'Not Confirmed' 
             ELSE  'Confirmed' END AS ConfirmStatus
  FROM tblConfirmationStatus;

Answer 1

CASE语句有两种选择 - 您发布的语句或:

SELECT CASE 
        WHEN Confirm_Status IS NULL OR Confirm_Status = 0 THEN 'Not Confirmed' 
        ELSE  'Confirmed' 
       END AS ConfirmStatus

但你可以使用:

SELECT CASE 
        WHEN Confirm_Status > 0 THEN 'Confirmed' 
        ELSE  'Not Confirmed' 
       END AS ConfirmStatus

NULL 如果没有值,那么检查大于零的值应该归入与零相同的类别.

Answer 2

SELECT IF((Confirm_Status IS NULL OR Confirm_Status = 0), 
           'Not Confirmed', 'Confirmed') AS ConfirmStatus
FROM tblConfirmationStatus;