Insertion of csv file data into mysql with duplication check

Question

I am trying to insert csv file data into mysql but i am not able to put duplication check on claim_refno,claim_parcelno please help me to how can i put duplication check on these two fields on insertion...please help

Here is my php code:

    <?php

session_start();
include"connection.php";
if (!isset($_SESSION['adm_id'])){
header("location: index.php");

}
else{ 



include "connection.php"; //Connect to Database

//Upload File
if (isset($_POST['submit'])) {
if (is_uploaded_file($_FILES['filename']['tmp_name'])) {
    $note= "<br/><span style='color:red;'>'" . "File ". $_FILES['filename']['name'] ."</span> uploaded successfully." ."";


}

  //Import uploaded file to Database

  //$firstRow = true;
   $j=0;


     $handle = fopen($_FILES['filename']['tmp_name'], "r");
     $firstRow = true;
     while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
        if($firstRow) { $firstRow = false; }
        else{

    $import="insert into tbl_claimdetail(claim_dateclaim,claim_clientname ,claim_account,claim_contract,claim_parcelno ,claim_refno,claim_datecollected,claim_coladdress ,claim_colpostcode,claim_counsineaddres,claim_conpostcode,claim_retailvalue,claim_claimvalue,claim_protitle,claim_reason ,claim_type,claim_repparcelno) values('$data[0]','$data[1]','$data[2]','$data[3]','$data[4]','$data[5]','$data[6]','$data[7]','$data[8]','$data[9]','$data[10]','$data[11]','$data[12]','$data[13]','$data[14]','$data[15]','$data[16]')"; 

    mysql_query($import) or die(mysql_error());
    $j++;   
 $msg = '<br/>Total <span style="color:red;">'.$j.'</span> Record has been added.';

   }
   }

  fclose($handle);





  }else {


  }




 include"header.php";
 include"leftmenu.php";
 include"html/upload.html";
 include"footer.php";
    }

 ?>