SQL 条件语句

第一种：

SELECT
CASE
     WHEN price IS NULL THEN 'Not yet priced'
     WHEN price < 10 THEN 'Very Reasonable Title'
     WHEN price >= 10 AND price < 20 THEN 'Coffee Table Title'
     ELSE 'Expensive book!'
     END AS "Price Category",
     CONVERT(varchar(20), title) AS "Shortened Title"
FROM pubs.dbo.titles
ORDER BY price

 第二种：

SELECT au_fname, au_lname,
   CASE state
      WHEN 'CA' THEN 'California'
      WHEN 'KS' THEN 'Kansas'
      WHEN 'TN' THEN 'Tennessee'
      WHEN 'OR' THEN 'Oregon'
      WHEN 'MI' THEN 'Michigan'
      WHEN 'IN' THEN 'Indiana'
      WHEN 'MD' THEN 'Maryland'
      WHEN 'UT' THEN 'Utah'
      END AS StateName
FROM pubs.dbo.authors
ORDER BY au_lname

本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/hbzhangjian/archive/2006/07/31/1003684.aspx

 

 

SELECT top 2 id, uid,cn,
   CASE len(cn)
      WHEN 3 THEN 'California'
      WHEN 2 THEN 'Kansas'     
      END AS StateName
FROM conf_users