这是一个asp.net的全文教程.里面还有数据库的数据.对初学者有很大的帮助

				
				
				
				
				
				Ch15-03-07.aspx SELECT表达式的IN子集查询
				
				Sub Page_Load(Obj As Object, e As EventArgs)
				Dim DSN As String, tSQL As String
				' 设置使用联机字符串 
				DSN = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & _
				     Server.MapPath("/ASP/Chap14/ASP.NET网页数据库.mdb") & ";"
				' 设置SQL语句
				tSQL = "SELECT * FROM UserDatas WHERE UserName IN " & _
				     "( SELECT TOP 2 UserName FROM UserDatas " & _
				     " GROUP BY UserName ORDER BY UserName DESC)"
				ShowResultSet(DSN, tSQL)
				End Sub