<?php
$db_host = "localhost";
$db_name = "webdb";
$db_user = "user";
$db_pass = "password";

try{
    $db_con = new PDO("mysql:host={$db_host};dbname=  {$db_name}",$db_user,$db_pass);
$db_con->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
}
catch(PDOException $e){
    echo $e->getMessage();
}

$id = $_REQUEST['del_id'];

/*$_REQUEST['del_id'] is this string: "[abcd]" square brackets    included*/

$stmt=$db_con->prepare("DELETE FROM profiles WHERE context=:id");
$stmt->execute(array(':id'=>$id));

?>