Imports System.Data.SqlClient

  Dim intCnt As Integer   
 Dim intI As Integer   
 Dim strQuery As String  
 Dim strValue As String = ""       
 Dim intValue As Integer        
 Dim objDS As New DataSet        
 Dim objDT As New DataTableFor intI = 0 To intCnt - 1           
 If strValue.Length = 0 
Then'Create query as per u r requirement.                    
strQuery = "Select max(LastPurPrc) from oitm"                Else                  
strQuery = "Select max(LastPurPrc) from oitm where LastPurPrc not in (" & strValue & ")"             

   End If        

   'Create dataset objDS using query strQuery        
    objDT = objDS.Tables(0)               
 If objDT.Rows.Count > 0 Then      
   intValue = objDT.Rows(0).Item(0)   
   If strValue.Length = 0 
Then    strValue = CStr(intValue)     
  Else                  

      strValue = strValue & "," & CStr(intValue)      
              End If         
       End If         
   Next          

  MessageBox.Show(intValue)