<?php
$sqlAdd = NULL;
if (!empty($_POST)) {
    if (isset($_POST['task_add'])) {
        $task = $_POST['task_add'];
        $taskDate = date('D.M.Y')." ".date('H:i:s');
        $sqlAdd = "INSERT INTO tasks(id, description, is_done, date_added) VALUES (?,?,?,?)";
    }
}
$db = new PDO("mysql:host=localhost;dbname=mydb;charset=utf8",'mysql','mysql');
if ($sqlAdd != NULL) {
    $dbh = $db->prepare($sqlAdd);
    $dbh->execute([NULL,$task,0,$taskDate]) or die ("Problems adding!");
}

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