[ 
 
 
left]Dim objConnect As OleDbConnection 
 
    Dim objCommand As OleDbCommand  
 
objConnect = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source =supermarket2003.mdb") 
  objConnect.Open() 
 
 
Dim sql As String 
txtnum  هو عبارة عن textbox في شاشة الvb و item_name, item_no هو اسم  fields في جدول ال product   
  
sql = "SELECT item_name FROM product where item_no = txtnum.text" 
         
        objCommand = New OleDbCommand(sql, objConnect) 
        
         
Dim objReader As OleDbDataReader = objCommand.ExecuteReader[/left 
عندما يصل الى هذه الجملة يعطي الخطأ التالي = No value given for one or more required parameters]