SQL SERVER¿ç·þÎñÆ÷²éѯ(SQL SERVER DBLINK)
--¿ç·þÎñÆ÷²éѯÈçÏ£º
SELECT a.*,b.stor_Name
from OPENROWSET('MSDASQL',
'DRIVER={SQL Server};SERVER=tom;UID=sa;PWD=123',
pubs.dbo.authors) AS a,stores b
ORDER BY a.au_lname, a.au_fname
--ÆäÖУ¬tomΪԶ³Ì·þÎñÆ÷Ãû£¬stores ÊDZ¾»úÊý¾Ý¿âpubsÖеıí
--ÐèҪעÒâµÄÊÇÈô¶þ¸ö±íÖеļǼÊýÄ¿²»Í¬»áµ¼ÖÂijһ¸ö±í²úÉúÍêÈ«ÖØ¸´µÄÐУ¬
--µÃµ½µÄ¼Ç¼¼¯µÄÐÐÊýΪ×µÄÄǸö±íÖеÄÐÐÊý
Èç:
insert into dbo.Kqmx_200704
select *
from openrowset('MSDASQL',
'DRIVER={SQL Server};SERVER=192.168.1.253;UID=sa;PWD=',
one.dbo.Kqmx_200704)
Áí:
Á¬½ÓÔ¶³Ì·þÎñÆ÷½øÐÐÊý¾Ý²éѯʱ¿ÉÒÔÕâô×ö£ºselect * from [**.**.**.**].test.dbo.t1
²»¹ý£¬²»³öÒâÍâµÄ»°»á±¨´í£ºÔÚ sysservers ÖÐδÄÜÕÒµ½·þÎñÆ÷ '**.*.**.**'¡£ÇëÖ´ÐÐ sp_addlinkedserver ÒÔ½«·þÎñÆ÷Ìí¼Óµ½ sysservers¡£
Ìí¼Ósysservers£ºexec sp_addlinkedserver 'srv_lnk','','SQLOLEDB','**.*.**.**'
ÔÙ²éѯ£ºselect * from srv_lnk.test.dbo.t1 £¨ÒòΪ¶¨ÒåÁË“±ðÃû”£¬ËùÒÔÕâ¶ù“±ðÃû”£©
³ý·ÇÁ½¸ö·þÎñÆ÷ÉϵĸÃÓû§µÄÃÜÂëÒ»Ñù£¬·ñÔò»á±¨£ºÓû§ '**' µÇ¼ʧ°Ü¡£
Ö¸¶¨µÇ¼Óû§£ºexec sp_addlinkedsrvlogin 'srv_lnk','false',null,'rUser','rPwd'
ÔÙ²éѯ£ºselect * from srv_lnk.test.dbo.t1£¬Èç¹ûÎÞÒâÍâµÄ»°¾ÍÓ¦¸ÃÊdzɹ¦µÄ
sp_addlinkedserver
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Exec sp_droplinkedsrvlogin server,Null
Exec sp_dropserver server
EXEC sp_addlinkedserver
@server= 'server ',--±»·ÃÎʵķþÎñÆ÷±ðÃû
@srvproduct= ' ',
@provider= 'SQLOLEDB ',
@datasrc= '10.23.11.28,3342 ' --Òª·ÃÎʵķþÎñÆ÷
EXEC sp_addlinkedsrvlogin
'server ', --±»·ÃÎʵķþÎñÆ÷±ðÃû
'false ',
NULL,
'la0001 ', --ÕʺÅ
'aaaaaa ' --ÃÜÂë
Á´½Ó·þÎñÆ÷ûÎÊÌâ,ÔÚ²éѯ·ÖÎöÆ÷ÀïÖ´ÐÐÀýÈç:select * from [192.168.0.119].fash.dbo.vwAllUserûÎÊÌâ.
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TA:
1,WANG
2,ZHANG
4,LI
TB:
1,100
2,200
3,400
1.left join ×óÁ¬½Ó--ÒÔ×ó±íΪ»ù×¼£¬ÓÒ±íÖÐûֵµÄ£¬ÔÚ½á¹û¼¯ÖÐÒÔnullÖµ´úÌæ¡£(select * from TA left join TB where TA.ID=TB.ID)
1,WANG,100
2,ZHANG,200
4,NULL
2.right join ÓÒÁ¬½Ó--ÒÔÓÒ±íΪ»ù×¼£¬×ó±íÖÐûֵµÄ£¬ÔÚ ......
string str = System.Configuration.ConfigurationManager.AppSettings["strconn"];
string sqlpwd = "select password from bg_user where username='" + username + "'";
MySqlConnection conn = new MySqlConnection(str);
MySqlCommand cmd=new MySqlCommand(sqlpwd,conn);
MySqlDataAdapter adr = new MySqlDataA ......
Case¾ßÓÐÁ½ÖÖ¸ñʽ¡£¼òµ¥Caseº¯ÊýºÍCaseËÑË÷º¯Êý¡£
--¼òµ¥Caseº¯Êý
CASE sex
WHEN '1' THEN 'ÄÐ'
WHEN '2' THEN 'Å®'
ELSE 'ÆäËû' END
--CaseËÑË÷º¯Êý
CASE WHEN sex = '1' THEN 'ÄÐ'
&nbs ......