Éè¼Æ¸ßЧsqlÒ»°ã¾Ñé̸ £¨×ª£©
1²»ÓÃÔÚsqlÓï¾äʹÓÃϵͳĬÈϵı£Áô¹Ø¼ü×Ö
2¾¡Á¿ÓÃexists ºÍ not exists ´úÌæ in ºÍ not in
ÕâÌõÔÚsql2005Ö®ºó£¬ÔÚË÷ÒýÒ»Ñù£¬Í³¼ÆÐÅÏ¢Ò»ÑùµÄÇé¿öÏ£¬exists £¬inЧ¹ûÊÇÒ»ÑùµÄ¡£
ÒÔAdventureWorksÊý¾Ý¿âΪÀý£¬²éѯÔÚHumanResources.EmployeeAddressÓеØÖ·µÄEmployeeÐÅÏ¢£¬
ÓÃin Óï¾äÈçÏ£º
SET STATISTICS IO ON
SELECT * from HumanResources.Employee
WHERE EmployeeID IN (SELECT EmployeeID from HumanResources.EmployeeAddress ea)
SET STATISTICS IO OFF
Ö´Ðкó£¬ÏûÏ¢ÈçÏ£º
(290 ÐÐÊÜÓ°Ïì)
±í'EmployeeAddress'¡£É¨Ãè¼ÆÊý1£¬Âß¼¶ÁÈ¡4 ´Î£¬ÎïÀí¶ÁÈ¡0 ´Î£¬Ô¤¶Á0 ´Î£¬lob Âß¼¶ÁÈ¡0 ´Î£¬lob ÎïÀí¶ÁÈ¡0 ´Î£¬lob Ô¤¶Á0 ´Î¡£
±í'Employee'¡£É¨Ãè¼ÆÊý1£¬Âß¼¶ÁÈ¡9 ´Î£¬ÎïÀí¶ÁÈ¡0 ´Î£¬Ô¤¶Á0 ´Î£¬lob Âß¼¶ÁÈ¡0 ´Î£¬lob ÎïÀí¶ÁÈ¡0 ´Î£¬lob Ô¤¶Á0 ´Î¡£
Ö´Ðмƻ®Èçͼ
ÓÃexists £¬Óï¾äÈçÏ£¬
SET STATISTICS IO ON
SELECT * from HumanResources.Employee
WHERE EXISTS(SELECT EmployeeID from HumanResources.EmployeeAddress ea
WHERE
HumanResources.Employee.EmployeeID=ea.EmployeeID)
SET STATISTICS IO OFF
Ö´Ðкó£¬ÏûÏ¢ÈçÏ£º
(290 ÐÐÊÜÓ°Ïì)
±í'EmployeeAddress'¡£É¨Ãè¼ÆÊý1£¬Âß¼¶ÁÈ¡4 ´Î£¬ÎïÀí¶ÁÈ¡0 ´Î£¬Ô¤¶Á0 ´Î£¬lob Âß¼¶ÁÈ¡0 ´Î£¬lob ÎïÀí¶ÁÈ¡0 ´Î£¬lob Ô¤¶Á0 ´Î¡£
±í'Employee'¡£É¨Ãè¼ÆÊý1£¬Âß¼¶ÁÈ¡9 ´Î£¬ÎïÀí¶ÁÈ¡0 ´Î£¬Ô¤¶Á0 ´Î£¬lob Âß¼¶ÁÈ¡0 ´Î£¬lob ÎïÀí¶ÁÈ¡0 ´Î£¬lob Ô¤¶Á0 ´Î¡£
Ö´Ðмƻ®Èçͼ£º
3¾¡Á¿²»ÓÃselect * from …..,¶øҪд×Ö¶ÎÃû select field1,field2,…
ÕâÌõûʲôºÃ˵µÄ£¬Ö÷ÒªÊÇ°´Ðè²éѯ£¬²»Òª·µ»Ø²»±ØÒªµÄÁкÍÐС£
4ÔÚsql ²éѯÖÐÓ¦¾¡Á¿Ê¹ÓÃË÷ÒýÁÐÀ´¼Ó¿ì²éѯËÙ¶È
5ÈκÎÔÚOrder by Óï¾äµÄ·ÇË÷ÒýÏî»òÕßÓмÆËã±í´ïʽ¶¼½«½µµÍ²éѯËÙ¶È
6ÈκÎÔÚwhere×Ó¾äÖÐʹÓÃis null »ò is not null µÄÓï¾ä²»ÔÊÐíʹÓÃË÷Òý£¬Ð§ÂʽϵÍ
7ͨÅä·û%ÔÚ´ÊÊ×ʱ£¬ÏµÍ³²»Ê¹ÓÃË÷
Ïà¹ØÎĵµ£º
µ±ÄãÕýÔÚ´¦Àí±»¶à¸öÕ¾µã£¨ÏñÔÚ¿ç¹ú¹«Ë¾Ìõ¼þÏ£©Ê¹ÓõĴóÊý¾Ý¿âʱ£¬ÄãÒ²Ðí»áÓöµ½±£Ö¤±í¸ñ¶ÔÏóΨһÐÔÕâÑùµÄ¼¬ÊÖÎÊÌâ¡£ÔÚÕâÖÖÇéÐÎÏ£¬¿ÉÄÜÖ»ÄÜ¿¿UNIQUEIDENTIFIERÀ´½â¾ö¡£UNIQUEIDENTIFIERÊÇÒ»¸ö±£´æÈ«¾ÖΨһ±êʶ·ûµÄGUIDÊý¾ÝÀàÐÍ¡£GUIDÊÇÒ»¸ö±£Ö¤Î¨Ò»µÄ¶þ½øÖÆÊý£¬Òò´Ë¼¸ºõûÓбðµÄ¼ÆËã»ú»á²úÉúͬһ¸öÖµ¡£
GUIDµÄΨһֵÊÇÓÉ¼Æ ......
¡¡¡¡×ܵÄÀ´Ëµ£¬MS SQL 2005µÄ°²È«ÐÔ±ÈSQL 2000ҪǿÉϲ»ÉÙ£¬²»¹ýĬÈÏÉèÖû¹ÊÇÓкÍÔÀ´Ò»ÑùµÄ©¶´£¬ÏÂÃæÎÒÃÇÀ´ÐÞ¸ÄÒ»ÏÂĬÈÏÉèÖá£
¡¡¡¡1¡¢ÐÞ¸ÄĬÈÏ£Ó£ÁÃÜÂë¡£
¡¡¡¡°²×°MSSQLʱʹÓûìºÏģʽ£¬µ±È»SAÃÜÂë×îºÃ²»ÄÜΪ¿Õ£¬ÔÚSQL2005ÖУ¬¿ÉÒÔ¶ÔSAÕâ¸ö³¬¼¶Óû§Ãû½øÐÐÐ޸Ļòɾ³ý¡£
use master
ALTER LOGIN [ ......
¡¡1¡¢varchar(max)¡¢nvarchar(max)ºÍvarbinary(max)Êý¾ÝÀàÐÍ×î¶à¿ÉÒÔ±£´æ2GBµÄÊý¾Ý£¬¿ÉÒÔÈ¡´útext¡¢ntext»òimageÊý¾ÝÀàÐÍ¡£
CREATE TABLE myTable
(
id INT,
content VARCHAR(MAX)
)
¡¡¡¡2¡¢XMLÊý¾ÝÀàÐÍ
¡¡¡¡XMLÊý¾ÝÀàÐÍÔÊÐíÓû§ÔÚSQL ServerÊý¾Ý¿âÖб£´æXMLƬ¶Î»òÎĵµ¡£
¡¡¡¡´íÎó´¦Àí Error Handling
¡ ......
1 Âß¼Êý¾Ý¿âºÍ±íµÄÉè¼Æ
¡¡¡¡Êý¾Ý¿âµÄÂß¼Éè¼Æ¡¢°üÀ¨±íÓë±íÖ®¼äµÄ¹ØϵÊÇÓÅ»¯¹ØϵÐÍÊý¾Ý¿âÐÔÄܵĺËÐÄ¡£Ò»¸öºÃµÄÂß¼Êý¾Ý¿âÉè¼Æ¿ÉÒÔΪÓÅ»¯Êý¾Ý¿âºÍÓ¦ÓóÌÐò´òÏÂÁ¼ºÃµÄ»ù´¡¡£
¡¡¡¡±ê×¼»¯µÄÊý¾Ý¿âÂß¼Éè¼Æ°üÀ¨ÓöàµÄ¡¢ÓÐÏ໥¹ØϵµÄÕ±íÀ´´úÌæºÜ¶àÁеij¤Êý¾Ý±í¡£ÏÂÃæÊÇһЩʹÓñê×¼»¯±íµÄһЩºÃ´¦¡£
A:ÓÉÓÚ±íÕ£¬Òò´Ë¿É ......
ÓÐЩʱºòÎÒÃÇÐèÒª²éѯÊý¾Ý¿âÖеÄʱ¼ä×ֶΣ¬ÀýÈç2009-11-11 11:11:11:111 ÕâÑùµÄʱ¼ä¸ñʽ¡£
¶øÎÒÃÇÓÐЩʱºò²»ÓðÑÕû¸öµÄ×ֶβéѯ³öÀ´£¬ÐèÒª°ÑÇ°ÃæµÄÈÕÆÚ½ØÈ¡³öÀ´£¬»òÕ߰ѺóÃæµÄʱ¼ä½ØÈ¡³öÀ´¡£
Õâ¸öʱºò¾ÍÒªÓõ½SQLÀïÃæµÄʱ¼äº¯ÊýÁË£º
select convert(char(10),×Ö¶ÎÃû,108) from ±íÃû
ÉÏÊöÓï¾äÊǽ«ºóÃæµÄʱ¼ä²éѯ³öÀ´£¬¸ñ ......