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1.²éÕÒÖظ´Êý¾Ý±íµÄidÒÔ¼°Öظ´Êý¾ÝµÄÌõÊý
select max(id) as nid,count(id) as Öظ´ÌõÊý from tableName
group by linkname Having Count(*) > 1
2.²éÕÒÖظ´Êý¾Ý±íµÄÖ÷¼ü
select max(id) as nid from tableName
group by linkname Having Count(id) > 1
3.ɾ³ýÖظ´µÄÊý¾Ý
delete from tableName
where id in (
select max(id) as nid from tableName
group by linkname Having Count(id) > 1
)
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party(Code,Name,Leader)
Code: Õþµ³´úÂë
Name: Õþµ³ ......
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1 :ÆÕͨSQLÓï¾ä¿ÉÒÔÓÃExecÖ´ÐÐ
eg: Select * from tableName
Exec( ......
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Student(S#,Sname,Sage,Ssex) ѧÉú±í
Course(C#,Cname,T#) ¿Î³Ì±í
SC(S#,C#,score) ³É¼¨±í
Teacher(T#,Tname) ½Ìʦ±í
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SQL:
using System.Data.SqlClient;
string sql = "server=.;uid=sa;pwd=;database=tablename;";
ACCESS:
using System.Data.OleDb;
string sql = "PROVIDER=Microsoft.Jet.OLEDB.4.0;DATA Source=" + HttpRuntime.AppDomainAppPath + "//App_Data//db.mdb";
HttpRuntime.AppDomainAppPath Ϊ¸ùĿ¼
......