VB.NET Updating data SQL using listview and dataset

Hello,

i am writing a Windows Forms application that allows users to manipulate data in a SQL 2008 database.

I use 3 listboxes and 1 listview on my form to hold the data from various tables in the database. The listboxes and listview are populated using a specific data-adapter that fill a specific dataset.

When I remove a row in the listview, i am searching the dataset for that particular row and I delete the row from the dataset.
After that I use the specific dataadapter again to send the update command to the SQL-server.
Unfortunately the data does not get updated but I do not get any errors.

I am using the following code:

        MsgBox("Really delete PI-tag: " & lstPoints.SelectedItems(0).Text & "?")
        For Each dr As DataRow In dsPoints.Tables(0).Rows
            If dr("tag_name") = lstPoints.SelectedItems(0).Text Then
                dr.Delete()
                dsPoints.AcceptChanges()
                Exit For
            End If
        Next
        For Each lstItem As ListViewItem In lstPoints.SelectedItems
            lstItem.Remove()
        Next
        pointsbuilder.GetDeleteCommand()
        adapPoints.Update(dsPoints, dsPoints.Tables(0).TableName.ToString)

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What am I doing wrong? I've searched the internet for hours and hours but am not able to solve it.... any help would be appreciated.
u795696Asked:
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sachitjainConnect With a Mentor Commented:
I guess you need to set updatecommand explicitly. Try doing that and let me know if you face issues.
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sachitjainCommented:
Can you try using dsPoints.Tables(0).Rows.Remove(dr) statement instead of  dr.Delete() statement?

See this link for example of Remove method of DataRowCollection object
http://msdn.microsoft.com/en-us/library/system.data.datarowcollection.remove.aspx

Also make sure that you are able to debug through statements inside your following condition
If dr("tag_name") = lstPoints.SelectedItems(0).Text Then
........


Might be possible for some reason that condition is never holding true
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u795696Author Commented:
Hi,

I've tried your suggestion but that still does not remove the row from the database. When I refresh my selection the data shows again.
I am sure that the row is found and removed from the dataset because the rows.count property of the dataset show a row less after the remove command.
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sachitjainCommented:
Can you display the code where your data adapter's updatecommand property is being set?
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u795696Author Commented:
In my first post, line 13 if that is what you mean...
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sachitjainCommented:
No that's your update method call

I mean you need to set updatecommand property for data adapter object. Something like this:
// Create the UpdateCommand.
    command = new SqlCommand(
        "UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName " +
        "WHERE CustomerID = @oldCustomerID", connection);

    // Add the parameters for the UpdateCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName");
    SqlParameter parameter = command.Parameters.Add(
        "@oldCustomerID", SqlDbType.NChar, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    adapter.UpdateCommand = command;

You could see following MSDN link for more details
http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldataadapter.updatecommand.aspx
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u795696Author Commented:
Ohw, that you mean :) Sorry, I'm new with working with databases via .NET

I understood that .NET has a thing called the SQLCommandBuilder that constructs all the necessary commands for you.

I've created an instance of the SQLCommandBuilder just after I filled the data-adapter wich filles the dataset that is used for the listview.

As you see at line 12 of my first post, I request the delete command from that specific SQLCommandbuilder and the next line should update my table...

At least that was what I was hoping for :-)
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u795696Author Commented:
I have created the following delete command:

        Dim delstring As String
        delstring = "Delete from tbllist_points where group_name='" & lboGroups.Text & _
                    "' and list_name='" & lboList_Area.Text & "' and list_area_name='" & lboArea.Text & "'"
        MsgBox(delstring)
        Try
            Dim ret
            Dim delCMD As SqlCommand = New SqlCommand(delstring, dbCon)
            ret = delCMD.ExecuteNonQuery()
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try

    End Sub

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This works OK, the record gets deleted from the database.

Is this the best way to perform the deletion of a row in the database? It is not using the dataset and the dataadapter in any way.
Can you also create a delete command for the dataadapter and then use the dataadapter to delete the row instead of using the code above?

I do not really care about performance as it is a very small database and only 2 or 3 people are working in it at the same time. It is also not used very often as it is a configuration database for another program.
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sachitjainCommented:
You could create InsertCommand, UpdateCommand and DeleteCommand for dataadapter object

http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldataadapter.deletecommand.aspx
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