在ADO.Net中使用聚合函数 [英] Using Aggregate functions in ADO.Net
问题描述
再次问好,
现在我已经掌握了ADO.NET的基础知识,我想在ado.net字符串命令中使用聚合函数。
Now that I have gotten the basics of ADO.NET, I would like to use aggregate functions within ado.net string commands.
我如何将聚合函数用于最简单的潜力?
How would I use aggregate functions to its simplest potential?
例如:
Public Sub BindData()
Dim connection As New OleDb.OleDbConnection(strDBFileX)
Dim dataadapter As New OleDb.OleDbDataAdapter("SELECT DISTINCT MAX(EmailAddresses.EmailAddressID)+1 as NewEMailAddressID , EmailAddresses.EmailAddress, EmailAddresses.AddressID FROM EmailAddresses WHERE EmailAddresses.AddressID=" & AddressIDTextBox.Text.ToString, connection)
Dim ds As New DataSet()
connection.Open()
dataadapter.Fill(ds, "EmailAddresses")
connection.Close()
EmailAddressesDataGridView.DataSource = ds
EmailAddressesDataGridView.DataMember = "EmailAddresses"
End Sub
欢迎任何用户在方便时改进此例程。
Any user is welcome to improve this routine at their convenience.
注意必须声明聚合函数。
Note that An aggregate function has to be declared.
用户想要完成的是通过提供Max聚合函数加1来添加新记录;因此,将创建一个新记录
What the user wants to accomplish is to add a new record by providing a Max aggregate function plus one; thus, a new record
或行。
问候,
JohnDBCTX
JohnDBCTX
jp
推荐答案
https://social.msdn.microsoft.com/Forums/en-US/home?forum=adodotnetdataproviders
https://social.msdn.microsoft.com/Forums/en-US/home?forum=adodotnetdataproviders
这是你应该发布的地方。
It's where you should post.
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