update not working

[qatarya3sal]

Imports System.XML
 
Public Class Form1
    Inherits System.Windows.Forms.Form
 
 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        transactions = New Transaction() {}
        GCC.Open()
    End Sub
 
    Private Sub btnLoad_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLoad.Click
        Dim action As String
        Dim country As String
        Dim month As Integer
        Dim year As Integer
        Dim amount As Double
 
        Dim document As XmlDocument
        Dim reader As XmlNodeReader
 
        Dim ofd As OpenFileDialog = New OpenFileDialog
        Dim result As DialogResult = ofd.ShowDialog
        If (result = DialogResult.Cancel) Then
            Return
        End If
 
        document = New XmlDocument
        document.Load(ofd.FileName)
 
        reader = New XmlNodeReader(document)
 
        reader.Read() 'skip root node
        While reader.Read()
            If (reader.Name = "transaction") Then
                reader.Read()
                action = reader.ReadElementString
                country = reader.ReadElementString
                month = reader.ReadElementString
                year = reader.ReadElementString
                amount = reader.ReadElementString
                ReDim Preserve transactions(transactions.Length)
                transactions(transactions.Length - 1) = New Transaction(action, country, month, year, amount)
            End If
        End While
 
        Try
 
            Dim t As Transaction
            For Each t In Me.transactions
 
                If t.getAction = "insert" Then
                    LNGAdapter.InsertCommand.CommandText = _
                    "INSERT INTO LNGproduction (fldCountry, fldMonth, fldYear, fldAmount ) VALUES('" & _
                t.getCountry & "', " & t.getMonth & ", " & t.getYear & ", " & t.getAmount & ")"
                    LNGAdapter.InsertCommand.ExecuteNonQuery()
 
                ElseIf (t.getAction = "update") Then
                    LNGAdapter.UpdateCommand.CommandText = _
                    "UPDATE LNGproduction SET fldAmount=" & t.getAmount & "WHERE fldCountry=" & " AND" & t.getCountry & "' AND fldMonth=" & t.getMonth & _
                    "AND fldYear=" & t.getYear
                    LNGAdapter.UpdateCommand.ExecuteNonQuery()
 
 
                ElseIf (t.getAction = "delete") Then
                    LNGAdapter.DeleteCommand.CommandText = _
                    "DELETE FROM LNGproduction WHERE fldCountry=" & " '" & t.getCountry & "' AND fldMonth=" & t.getMonth & _
                    " AND fldYear=" & t.getYear
                    LNGAdapter.DeleteCommand.ExecuteNonQuery()
 
                End If
            Next
 
        Catch oleDbExceptionParameter As System.Data.OleDb.OleDbException
            Console.WriteLine(oleDbExceptionParameter)
 
        End Try
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
 
        LNGAdapter.SelectCommand.CommandText = TextBox1.Text
        LngDataSet.Clear()
        LNGAdapter.Fill(LngDataSet, "LNGproduction")
        DataGrid1.SetDataBinding(LngDataSet, "LNGproduction")
 
    End Sub
 
End Class

The update not working with me i don't know why

[debasisdas]

can you explain please what does this line of code means

"UPDATE LNGproduction SET fldAmount=" & t.getAmount & "WHERE fldCountry=" & " AND" & t.getCountry & "' AND fldMonth=" & t.getMonth & _
                    "AND fldYear=" & t.getYear
 

What is the value for fldCountry ?

[Plater]

can you explain please what does this line of code means

"UPDATE LNGproduction SET fldAmount=" & t.getAmount & "WHERE fldCountry=" & " AND" & t.getCountry & "' AND fldMonth=" & t.getMonth & _
                    "AND fldYear=" & t.getYear
 

What is the value for fldCountry ?

That looks like a pretty good candidate for why the update fails.

[qatarya3sal]

can you explain please what does this line of code means

"UPDATE LNGproduction SET fldAmount=" & t.getAmount & "WHERE fldCountry=" & " AND" & t.getCountry & "' AND fldMonth=" & t.getMonth & _
                    "AND fldYear=" & t.getYear
 

What is the value for fldCountry ?

Is string ... i don't know where the mistake

[Motoma]

Is string ... i don't know where the mistake

What my compatriots are alluding to is that you are attempting to perform an UPDATE which has a malformed WHERE clause. Your WHERE clause is malformed because you never specify a value for fldCountry.

[Plater]

I'm gonna try and bold the problem areas:

"UPDATE LNGproduction " _
"SET "_
"fldAmount= " & t.getAmount & _
"WHERE " _
"fldCountry =" & _
" AND " & t.getCountry & _
"' AND fldMonth=" & t.getMonth & _
"AND fldYear=" & t.getYear

As you notice there appears to be an extra "AND" in there, assuming that fldCountry should be tested with t.getCountry