CASE input_expression
    WHEN when_expression THEN result_expression
        [ ...n ]
    [ 
        ELSE else_result_expression
    END

SELECT Eno, Ename, Sex = CASE SubString(Pno, 2, 1) 
       WHEN '1' THEN '男' WHEN '2' THEN '女' ELSE '' END
FROM Empl

使用 CASE 的條件式資料處理
CASE 函數可用來運算多個條件 (Condition)，並針對每個條件傳回一個數值。CASE 函數的常見用法是以較具可讀性的數值來取代程式碼或縮寫 (Abbreviation)。下列查詢將使用 CASE 函數來將書籍類別重新命名，以便讓它們更好瞭解。    USE pubs
SELECT
   CASE type
      WHEN 'popular_comp' THEN 'Popular Computing'
      WHEN 'mod_cook' THEN 'Modern Cooking'
      WHEN 'business' THEN 'Business'
      WHEN 'psychology' THEN 'Psychology'
      WHEN 'trad_cook' THEN 'Traditional Cooking'
      ELSE 'Not yet categorized'
   END AS Category, 
CONVERT(varchar(30), title) AS "Shortened Title", 
price AS Price
FROM titles
WHERE price IS NOT NULL
ORDER BY 1    以下為結果集：    category            shortened title                Price   
------------------- ------------------------------ ------- 
Business            Cooking with Computers: Surrep 11.95   
Business            Straight Talk About Computers  19.99   
Business            The Busy Executive's Database  19.99   
Business            You Can Combat Computer Stress 2.99    
Modern Cooking      Silicon Valley Gastronomic Tre 19.99   
Modern Cooking      The Gourmet Microwave          2.99    
Popular Computing   But Is It User Friendly?       22.95   
Popular Computing   Secrets of Silicon Valley      20.00   
Psychology          Computer Phobic AND Non-Phobic 21.59   
Psychology          Emotional Security: A New Algo 7.99    
Psychology          Is Anger the Enemy?            10.95   
Psychology          Life Without Fear              7.00    
Psychology          Prolonged Data Deprivation: Fo 19.99   
Traditional Cooking Fifty Years in Buckingham Pala 11.95   
Traditional Cooking Onions, Leeks, and Garlic: Coo 20.95   
Traditional Cooking Sushi, Anyone?                 14.99       (16 row(s) affected)

引言: 再請問一下，那如果WHEN 後面要對兩個欄位下判斷要如何下？

引言: 各為大人: 請問case 是否為MS-SQL獨有語法, 若TABLE 為 .DBF 可否於QUERY中下此語法呢? 若使用 .DBF又得用QUERY是否有其它替代方案呢