Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

SQL Ìõ¼þÓï¾ä

µÚÒ»ÖÖ£º
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
 µÚ¶þÖÖ£º
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
±¾ÎÄÀ´×ÔCSDN²©¿Í£¬×ªÔØÇë±êÃ÷³ö´¦£ºhttp://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


Ïà¹ØÎĵµ£º

sqlÓï¾äÓÅ»¯

SQLÓï¾äµÄÓÅ»¯¾ÍÊǽ«ÐÔÄܽϵ͵ÄSQLÓï¾äת»»´ï³ÉͬÑùÄ¿µÄÐÔÄÜÓÅÒìµÄSQLÓï¾ä
ÏÂÃæÎÒÃÇÒ»ÆðÀ´¿´¿´Ò»Ð©¿ÉÒÔÓÅ»¯SQLµÄ·½·¨£¬Ï£Íû´ó¼Ò¶àÌá³öÒâ¼ûÎÒÃǹ²Í¬Ñ§Ï°»òÕßÊÇ´ó¼ÒÓÐʲôºÃµÄÓÅ»¯·½·¨¿ÉÒÔÌá³öÀ´¹²Ïíһϡ£
µÚÒ»ÖÖÓÅ»¯£¨Ê¹ÓÃÖ¸¶¨ÁдúÌæ”*”£©
       ʹÓÓ*”¿ÉÒÔ½µµÍ±àдSQLÓï ......

Oracle Sql ÐÔÄÜÓÅ»¯

1£©²»Öª´ó¼ÒÊÇ·ñϲ»¶Ê¹ÓÑNOT IN’ÕâÑùµÄ²Ù×÷£¬Èç¹ûÊÇ£¬ÄǾ¡Á¿Ê¹ÓÃ(NOT) EXISTS Ìæ´ú
2£©ÔÚº£Á¿²éѯʱ¾¡Á¿ÉÙÓøñʽת»»¡£
3£©²éѯº£Á¿Êý¾ÝÊÇ£¬¿ÉÒÔʹÓÃoptimizer['ɔptimaizə] hints£¬ÀýÈç/*+ORDERED */
¾¡Á¿ÉÙÓÃIN²Ù×÷·û£¬»ù±¾ÉÏËùÓеÄIN²Ù×÷·û¶¼¿ÉÒÔÓÃEXISTS´úÌæ¡£
²»ÓÃNOT IN²Ù×÷·û£¬¿ÉÒÔ ......

Flat hierarchyid in SQL Server 2008

ÔÚSQL Server 2008ÖÐÒýÈëÁËhierarchyidÀ´´¦ÀíÊ÷×´½á¹¹¡£ÏÂÃæ¼òµ¥¾ÍÒÔAdventureWorks(ÎÞhierarchyid)ºÍAdventureWorks2008(ÓÐhierarchyid)ÀïµÄHumanResources.EmployeeΪÀý£¬À´ËµÃ÷Ò»ÏÂÔÚеÄhierarchyidÖÐÈçºÎ½øÐÐflat»¯µÄdimension³éÈ¡¡£
AdventureWorksÊÇ΢ÈíΪSQL ServerÌṩµÄÊý¾Ý¿âÐéÄâ°¸Àý¡£
AdventureWorksÖÐËùÒªµ ......

SQL²éѯÊý¾Ý¿âÖÐÿÕűíµÄ¼Ç¼Êý

±¾ÎÄÀ´×Ô£ºhttp://hi.baidu.com/darkroot/blog/item/7b74be2cf06d76e78b139903.html
declare   @tbName     nvarchar(500)
declare   @ct      int  
declare   @csql   nvarchar(500)  
declare &n ......

SQL ²éѯÓï¾äʹÓÃ

Ò»¡¢¼òµ¥²éѯ
¡¡¡¡ ¼òµ¥µÄTransact-SQL²éѯֻ°üÀ¨Ñ¡ÔñÁÐ±í¡¢from×Ó¾äºÍWHERE×Ӿ䡣
ËüÃÇ·Ö±ð˵Ã÷Ëù²éѯÁС¢²éѯµÄ
±í»òÊÓͼ¡¢ÒÔ¼°ËÑË÷Ìõ¼þµÈ¡£
ÀýÈ磬ÏÂÃæµÄÓï¾ä²éѯtesttable±íÖÐÐÕÃûΪ“ÕÅÈý”µÄnickname×ֶκÍemail×ֶΡ£
SELECT nickname,email
from testtable WHERE name='ÕÅÈý'
(Ò»)Ñ¡ÔñÁбí
¡ ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ