¹ØÓÚSQLÖÐÓÃJoin in ²éѯµÄÓ÷¨
ÍâÁª½Ó:ÍâÁª½Ó¿ÉÒÔÊÇ×óÏòÍâÁª½Ó¡¢ÓÒÏòÍâÁª½Ó»òÍêÕûÍⲿÁª½Ó¡£
ÔÚ from ×Ó¾äÖÐÖ¸¶¨ÍâÁª½Óʱ£¬¿ÉÒÔÓÉÏÂÁм¸×鹨¼ü×ÖÖеÄÒ»×éÖ¸¶¨£º
LEFT JOIN »ò LEFT OUTER JOIN;
×óÏòÍâÁª½ÓµÄ½á¹û¼¯°üÀ¨ LEFT OUTER ×Ó¾äÖÐÖ¸¶¨µÄ×ó±íµÄËùÓÐÐУ¬¶ø²»½ö½öÊÇÁª½ÓÁÐËùÆ¥ÅäµÄÐС£Èç¹û×ó±íµÄijÐÐÔÚÓÒ±íÖÐûÓÐÆ¥ÅäÐУ¬ÔòÔÚÏà¹ØÁªµÄ½á¹û¼¯ÐÐÖÐÓÒ±íµÄËùÓÐÑ¡ÔñÁбíÁоùΪ¿ÕÖµ¡£
Ïà¹ØÎĵµ£º
windows ¼¯³ÉÑéÖ¤£º
<connectionStrings>
<add name="ConnectionStr" connectionString="Data Source=CAIPENG-PC;database=Test;Integrated Security=SSPI" providerName="System.Data.SqlClient"/>
</connectionStrings>
»òÕß
<connectionStrings>
<add name=" ......
Ò»¡¢ÉîÈëdz³öÀí½âË÷Òý½á¹¹
¡¡¡¡Êµ¼ÊÉÏ£¬Äú¿ÉÒÔ°ÑË÷ÒýÀí½âΪһÖÖÌØÊâµÄĿ¼¡£Î¢ÈíµÄsql serverÌṩÁËÁ½ÖÖË÷Òý£º¾Û¼¯Ë÷Òý£¨clustered index£¬Ò²³Æ¾ÛÀàË÷Òý¡¢´Ø¼¯Ë÷Òý£©ºÍ·Ç¾Û¼¯Ë÷Òý£¨nonclustered index£¬Ò²³Æ·Ç¾ÛÀàË÷Òý¡¢·Ç´Ø¼¯Ë÷Òý£©¡£ÏÂÃæ£¬ÎÒÃǾÙÀýÀ´ËµÃ÷һϾۼ¯Ë÷ÒýºÍ·Ç¾Û¼¯Ë÷ÒýµÄÇø±ð£º
¡¡¡¡Æäʵ£¬ÎÒÃǵĺºÓï×ÖµäµÄÕ ......
Ò»¡¢»ù´¡
1¡¢ËµÃ÷£º´´½¨Êý¾Ý¿â
CREATE DATABASE database-name
2¡¢ËµÃ÷£ºÉ¾³ýÊý¾Ý¿â
drop database dbname
3¡¢ËµÃ÷£º±¸·Ýsql server
--- ´´½¨ ±¸·ÝÊý¾ÝµÄ device
USE master
EXEC sp_addumpdevice 'disk', 'testBack', 'c:\mssql7backup\MyNwind_1.dat'
--- ¿ªÊ¼ ±¸·Ý
BACKUP DATABASE pubs TO testBack
4¡¢Ëµ ......
ºÜ¶à¼¼Êõ°®ºÃÕߵĵçÄÔÉÏ×ÜÊǰ²×°Á˺ܶàÈí¼þ£¬°üÀ¨Ó¦ÓÃÈí¼þ¡¢¿ª·¢¹¤¾ßÈí¼þ¼°Êý¾Ý¿âÈí¼þ£¬µ«ÊÇËæ×Åʱ¼äµÄÁ÷ÊÅ£¬ÂýÂýµØµçÄÔÉÏ×°µÄÈí¼þÒѾ³¬³öÁ˵çÄÔ±¾ÉíËùÄÜ
³ÐÔØµÄÁ¿ÁË£¬Òò¶ø³öÏÖÁ˵çÄÔÔËÐÐËÙ¶ÈÂýµÈÎÊÌ⡣ͬʱ£¬Ò²ÓÐһЩµ¥Î»»ò¸öÈ˵ĵçÄÔÓÉÓÚ³ö³§Äê´úÓÐЩ¾ÃÔ¶£¬¼´Ê¹Ö»°²×°Ò»ÖÖ»ò¼«ÉÙÊýÈí¼þʱҲ»áÏÔʾ³öÔËÐÐËÙ¶ÈÂý
µÄÏÖÏó¡£ ......