Checking Data in MYSQL before an insert.

[superdude]

I am trying to make a form that certain fields will be checked against the data in mysql, this is to avoid duplicates.  Below is the code I am trying to use.  It is to verify that a phone number is not already in database.  i first checked that it was there, and then i tried to check it against the database, however it is simply going to my not uploaded warning.  What can I do?  Is there maybe a better way to do this?  as this is one of many checks like this. Note: this is not a primary nor will be.

if(empty($_POST['home_phone'])){$errors[]='Home Phone Required';
    }else{
    $hp=trim($_POST['home_phone']); }
    if($hp){
      //connects to databse
      require_once('./db_config.php');
      $hpq="SELECT home_phone FROM leads where home_phone='$hp'";
      $hpresult= mysql_query($hpq) or trigger_error("Query: $hpq\n<br/>MYSQL Error:".mysql_errno());
      if (mysql_num_rows($hpresult)==0){$home_phone=trim($_POST['home_phone']);}Else{
      $errors[]='Duplicate Lead';}
      ;}


  //If no errors
  if(empty($errors))

[mr. big]

This part looks good to me. I'm pretty much a noob but I use a nearly identical code, only the last line of mine makes the insertion query using $hp instead of giving $_POST['home_phone'] a second variable name.

Might be in another part of the code.

[superdude]

Here is the coding modified a bit, still no better result.  Seems to always come up an error, even when one does not exsist.  Hmmmmm...

//home phone
    if(empty($_POST['home_phone'])){$errors[]='Home Phone Required';
    }else{
        if($_POST['home_phone']);{
      //connects to databse
      require_once('./db_config.php');
      $hpq="SELECT home_phone FROM leads where home_phone='$home_phone'";
      $hpresult= mysql_query($hpq) //or trigger_error("Query: $hpq\n<br/>MYSQL Error:".mysql_errno())
      ;}
      if(mysql_num_rows($hpresult)==0){
      $home_phone=trim($_POST['home_phone']);}Else
      {$errors[]='Duplicate Lead';}
      }

[fenway]

An error how?