I am new to VB. Currently i am doing a Stock manage program with VB and SQL 2008.

When Receive new stock from Supplier,I put recive item in a winform with DataGrid view. some thing like this

**Item  Description Received Qty UnitPrice Total**
  1001  Acer Laptop  10          455       4550
  1005  Monitor      20          100       2000

this data insert to purchase details table and I have another table for Stock call Stock.
now I want to do when after enter the data and when click save button ReceiveQty value add to CurrentStock colunm in Stock table.
in this case how can i do this. I hope you could understand what i try to do here.
if you want to see my code I can past here.
Thanks all!

Update CurrentStock after Save data.
Do save and update at the same time.
You can post your code here to give more information.

Here is my code

I want to Add this value (Dim receivedQty As String = DGGRN.Rows(I).Cells(3).Value) to in Stock table CurrentStock Colunm value with particular itemcode


Private Sub ButtonSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonSave.Click

        'Connecting to SQL Server using VB code
        Dim MyConnection As SqlConnection = Nothing
        Dim MyTransaction As SqlTransaction = Nothing

            'Connect to Database Server using connection string

            MyConnection = New SqlConnection("Data Source=my-pc;Initial Catalog=IKStock;Integrated Security=True")
            MyTransaction = MyConnection.BeginTransaction

            'Insert inside Good Recived note to Puruchase Table
            Dim SQL As String = "insert into Purchase (SupplierCode,Supplier,SupplerAddress,Date,InvoiceNumber,QuotationNumber,PONumber,ManualGRNno,GRNTotal) values (@0,@1,@2,@3,@4,@5,@6,@7,@8)"
            Dim CMD1 As New SqlCommand
            CMD1.Connection = MyConnection
            CMD1.Transaction = MyTransaction
            CMD1.CommandText = SQL
            CMD1.Parameters.AddWithValue("@0", TextBoxSupplierCode.Text) 'text box data insert in to Purchase Table columns
            CMD1.Parameters.AddWithValue("@1", ComboBoxSupplier.Text)
            CMD1.Parameters.AddWithValue("@2", TextBoxSupplerAddress.Text)
            CMD1.Parameters.AddWithValue("@3", DateTimePickerDate.Text)
            CMD1.Parameters.AddWithValue("@4", TextBoxInvoiceNumber.Text)
            CMD1.Parameters.AddWithValue("@5", TextBoxQuotationNo.Text)
            CMD1.Parameters.AddWithValue("@6", TextBoxPOno.Text)
            CMD1.Parameters.AddWithValue("@7", TextBoxManualGRNno.Text)
            CMD1.Parameters.AddWithValue("@8", TextBoxIncTotal.Text)

            'Get GRN code from Purchase table to purchase table
            SQL = "select max(GRNCode) as MAXID from Purchase"
            Dim CMD2 As New SqlCommand
            CMD2.Connection = MyConnection
            CMD2.Transaction = MyTransaction
            CMD2.CommandText = SQL
            Dim GRNCode As Long = CMD2.ExecuteScalar()

            'insert the datagridview details to PurchaseDetails Table

            Dim I As Integer
            For I = 0 To DGGRN.Rows.Count - 1

                Dim item As String = DGGRN.Rows(I).Cells(0).Value
                Dim description As String = DGGRN.Rows(I).Cells(1).Value
                Dim category As String = DGGRN.Rows(I).Cells(2).Value
                Dim receivedQty As String = DGGRN.Rows(I).Cells(3).Value
                Dim unitprice As Decimal = DGGRN.Rows(I).Cells(4).Value
                Dim nbt As String = DGGRN.Rows(I).Cells(5).Value
                Dim vat As String = DGGRN.Rows(I).Cells(6).Value
                Dim linetotal As Decimal = DGGRN.Rows(I).Cells(7).Value
                Dim remarks As String = DGGRN.Rows(I).Cells(9).Value

                'Insert Above Variable data to Purchase Details table
                Dim CMD3 As New SqlCommand
                SQL = "insert into PurchaseDetails (GRNCode,ItemCode,Description,ReceivedQty,NewUnitPrice,NBT,VAT,LineTotal,Remarks,Category) values (@0 ,@1 ,@2 ,@3 ,@4 ,@5 ,@6 ,@7 ,@8,@9)"
                CMD3.Connection = MyConnection
                CMD3.Transaction = MyTransaction
                CMD3.CommandText = SQL
                CMD3.Parameters.AddWithValue("@0", GRNCode)
                CMD3.Parameters.AddWithValue("@1", item)
                CMD3.Parameters.AddWithValue("@2", description)
                CMD3.Parameters.AddWithValue("@3", receivedQty)
                CMD3.Parameters.AddWithValue("@4", unitprice)
                CMD3.Parameters.AddWithValue("@5", nbt)
                CMD3.Parameters.AddWithValue("@6", vat)
                CMD3.Parameters.AddWithValue("@7", linetotal)
                CMD3.Parameters.AddWithValue("@8", remarks)
                CMD3.Parameters.AddWithValue("@9", category)




            'close connection

            'Show Message After Save Data
            MsgBox("Successfully Saved New GRN", MsgBoxStyle.OkOnly, "Save Success")

            'After Save Reset all field
            ComboBoxSupplier.SelectedIndex = 0
            TextBoxSupplerAddress.Text = ""
            TextBoxInvoiceNumber.Text = ""
            TextBoxQuotationNo.Text = ""
            TextBoxPOno.Text = ""
            TextBoxManualGRNno.Text = ""
            ComboBoxItem.Text = ""
            ComboBoxItemDis.Text = ""
            TextBoxReciveQty.Text = ""
            TextBoxUnitPrice.Text = ""
            TextBoxNBT.Text = ""
            TextBoxVAT.Text = ""
            TextBoxRemarks.Text = ""

        Catch ex As Exception
            If MyTransaction IsNot Nothing Then

            End If

            If MyTransaction IsNot Nothing Then
                If MyConnection.State = ConnectionState.Open Then

                End If
            End If
            MsgBox(ex.Message, MsgBoxStyle.Critical Or MsgBoxStyle.OkOnly)

        End Try

    End Sub