How to check if two columns match from joined tables?

[robato1981]

I’m trying to check two see if the customer is within range of the realtor and if so to email that realtor. So far I got to the point where I can calculate the distance in the query. So since I can match those that are in distance how to check if two columns match? I need to know if two columns match what is the best way for this to be done?

$realtCust = $db->prepare("SELECT
    rid
  , rEmail
  ,id
  , eMail
FROM realtors r
    LEFT JOIN
  customers c
    ON pow(clatitude-rlatitude, 2) + pow(clongitude-rlongitude, 2) < pow(100/110.25, 2)
ORDER BY rid, id");

$realtCust->execute();
$realtCust->rowCount();


$realtCust_row = $realtCust ->fetch(PDO::FETCH_ASSOC);



$rcArray = array(
     [$realtCust_row['rid'],$realtCust_row['rEmail']],
     [$realtCust_row['id'],$realtCust_row['eMail']],

);
foreach( $rcArray as list( ,$rcEmail)) {
    //echo "$a\n";

     echo $rcArray;
}