擴展SELECT IF語句

Question

我使用SELECT IF語句將數據從我的數據庫翻譯：如果狀態爲1的語句顯示Status one

IF(status = 1, 'Status one', 'Status two') 

。如果狀態是別的，則說明顯示Status two。

我想延長這一說法，並顯示：

IF status = 1, 'Status one' 
IF status = 2, 'Status two' 
IF status = 3, 'Status three' 
IF status = 4, 'Status four' 

是否有人知道我該怎麼做呢？

Answer 1

你也可以使用一個CASE表達：

SELECT 
    CONCAT('Status ', 
     CASE WHEN status = 1 THEN 'one' 
      WHEN status = 2 THEN 'two' 
      WHEN status = 3 THEN 'three' 
      WHEN status = 4 THEN 'four' END) AS label 
FROM yourTable 

Demo

Answer 2

像這樣的東西應該工作：

SELECT 
    (CASE 
     WHEN status = 1 THEN 'Status one' 
     WHEN status = 2 THEN 'Status two' 
     WHEN status = 3 THEN 'Status three' 
     WHEN status = 4 THEN 'Status four' 
     ELSE 'Incorrect Option' 
    END) AS statustext 
FROM yourtable; 

按YSTH的評論，這是更緊湊，可能更有效：

SELECT 
    (CASE status 
     WHEN 1 THEN 'Status one' 
     WHEN 2 THEN 'Status two' 
     WHEN 3 THEN 'Status three' 
     WHEN 4 THEN 'Status four' 
     ELSE 'Incorrect Option' 
    END) AS statustext 
FROM yourtable; 

謝謝你！