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RichardKline

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How do I use SqlDataAdapter.Update to work properly

THis is my first attempt to use the Update method of SqlDataAdapter.    I've found several examples on the web but am unable to get my code to work.     The current version is, probably, a bad combination of examples.

No error is generated.  But the SQL Server table is never updated.
The code does retrieve the needed information.  The for loop works fine.   The SendNotification() function returns true.

Any thought on what might be wrong?
Thank you.
Dim sqlSelect As String = "SELECT [uid] " & _
        "      ,[epk] " & _
        "      ,[user_id] " & _
        "      ,[password] " & _
        "      ,[firstName] " & _
        "      ,[lastName] " & _
        "      ,[email] " & _
        "      ,[genDate] " & _
        "      ,[userOrigin] " & _
        "      ,[sendNotification] " & _
        "      ,[emailTemplate] " & _
        "      ,[snapShotGuid] " & _
        "      ,[NotificationSentOn] " & _
        "  FROM [bbprocessing].[dbo].[UrNewUsers] " & _
        "  WHERE [snapShotGuid] = @snapShotGuid" & _
        "       AND [sendNotification]=1 " & _
        "       AND [NotificationSentOn] < @NotificationSentOn"
 
        Dim sqlUpdate As String = "UPDATE [bbprocessing].[dbo].[UrNewUsers] " & _
            "   SET [sendNotification] = 0 " & _
            "      ,[NotificationSentOn] = @NotificationSentOn " & _
            " WHERE [uid] = @uid "
 
        Dim cn As New SqlConnection
        cn = clsMakeCn.newProc
        Dim da As New SqlDataAdapter(sqlSelect, cn)
 
        With da.SelectCommand.Parameters
            .Clear()
            .AddWithValue("@snapShotGuid", GuidToProcess)
            .AddWithValue("@NotificationSentOn", New DateTime(2000, 1, 1))
        End With
 
        Dim updateCmd As New SqlCommand(sqlUpdate, cn)
        da.UpdateCommand = updateCmd
        da.AcceptChangesDuringUpdate = True
 
        Dim oDataSet As New DataSet
        Try
            da.Fill(oDataSet, "Notifications")
        Catch ex As Exception
            Dim emsg As String = ex.Message
        End Try
 
        For Each dr As DataRow In oDataSet.Tables("Notifications").Rows
            If SendNotification(dr) Then
                Try
                    With da.UpdateCommand.Parameters
                        .Clear()
                        .AddWithValue("@NotificationSentOn", Now)
                        .AddWithValue("@SendNotification", 0)
                        .AddWithValue("@uid", dr("uid"))
                    End With
                    da.UpdateCommand.ExecuteNonQuery()
                Catch ex As Exception
                    Dim eMsg As String = ex.Message
                End Try
            Else
                Dim eMsg As String = "Unable to Send Notification"
            End If
        Next

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RichardKline

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Thank you.

I had to make a couple of small changes to avoid errors  with UpdateCmd.Parameters add lines and Dim changed As Integer = da.Update(oDataSet, "Notifications")

So the code operates without error
    but there is still no change in the SQL table values.



        Dim cn As New SqlConnection
        cn = clsMakeCn.newProc
        Dim da As New SqlDataAdapter(sqlSelect, cn)
 
        With da.SelectCommand.Parameters
            .Clear()
            .AddWithValue("@snapShotGuid", GuidToProcess)
            .AddWithValue("@NotificationSentOn", New DateTime(2000, 1, 1))
        End With
 
        Dim updateCmd As New SqlCommand(sqlUpdate, cn)
        With updateCmd.Parameters
            .Add("NotificationSentOn", SqlDbType.DateTime).SourceColumn = "NotificationSentOn"
            .Add("uid", SqlDbType.Int).SourceColumn = "uid"
        End With
 
        da.UpdateCommand = updateCmd
        da.AcceptChangesDuringUpdate = True
 
        Dim oDataSet As New DataSet
        Try
            da.Fill(oDataSet, "Notifications")
        Catch ex As Exception
            Dim emsg As String = ex.Message
        End Try
 
        For Each dr As DataRow In oDataSet.Tables("Notifications").Rows
            If SendNotification(dr) Then
                Try
                    Dim changed As Integer = da.Update(oDataSet, "Notifications")
                Catch ex As Exception
                    Dim eMsg As String = ex.Message
                End Try
            Else
                Dim eMsg As String = "Unable to Send Notification"
            End If
        Next

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Can you add a breakpoint to the da.Update line, and check the value of dr.RowState. The Update method will only execute the Update command on rows that have a RowState of Modified.
Found it.  Silly omission.  Neglected to se the new values before updating.
                dr("SendNotification") = 0
                dr("NotificationSentOn") = Now

The complete and working new code is below.
        Dim sqlSelect As String = "SELECT [uid] " & _
        "      ,[epk] " & _
        "      ,[user_id] " & _
        "      ,[password] " & _
        "      ,[firstName] " & _
        "      ,[lastName] " & _
        "      ,[email] " & _
        "      ,[genDate] " & _
        "      ,[userOrigin] " & _
        "      ,[sendNotification] " & _
        "      ,[emailTemplate] " & _
        "      ,[snapShotGuid] " & _
        "      ,[NotificationSentOn] " & _
        "  FROM [bbprocessing].[dbo].[UrNewUsers] " & _
        "  WHERE [snapShotGuid] = @snapShotGuid" & _
        "       AND [sendNotification]=1 " & _
        "       AND [NotificationSentOn] < @NotificationSentOn"
 
        Dim sqlUpdate As String = "UPDATE [bbprocessing].[dbo].[UrNewUsers] " & _
            "   SET [sendNotification] = 0 " & _
            "      ,[NotificationSentOn] = @NotificationSentOn " & _
            " WHERE [uid] = @uid "
 
        Dim cn As New SqlConnection
        cn = clsMakeCn.newProc
        Dim da As New SqlDataAdapter(sqlSelect, cn)
 
        With da.SelectCommand.Parameters
            .Clear()
            .AddWithValue("@snapShotGuid", GuidToProcess)
            .AddWithValue("@NotificationSentOn", New DateTime(2000, 1, 1))
        End With
 
        Dim updateCmd As New SqlCommand(sqlUpdate, cn)
        With updateCmd.Parameters
            .Clear()
            .Add("NotificationSentOn", SqlDbType.DateTime).SourceColumn = "NotificationSentOn"
            .Add("uid", SqlDbType.Int).SourceColumn = "uid"
        End With
 
        da.UpdateCommand = updateCmd
        da.AcceptChangesDuringUpdate = True
 
        Dim oDataSet As New DataSet
        Try
            da.Fill(oDataSet, "Notifications")
        Catch ex As Exception
            Dim emsg As String = ex.Message
        End Try
 
        For Each dr As DataRow In oDataSet.Tables("Notifications").Rows
            If SendNotification(dr) Then
                dr("SendNotification") = 0
                dr("NotificationSentOn") = Now
                Try
                    Dim changed As Integer = da.Update(oDataSet, "Notifications")
                Catch ex As Exception
                    Dim eMsg As String = ex.Message
                End Try
            Else
                Dim eMsg As String = "Unable to Send Notification"
            End If
        Next

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Also neglected to say "Thanks!"   I appreciate the Excellent help.