使用ajax在服务器端php脚本上传递数据进行访问

Question

Okay my problem is the following:

I am trying to access a variable I defined with javascript in my executing php-script.

// CLIENT SIDE CODE

function deleteEntry() {
      var action = '_includes/deleteEntry.php';
      var method = 'post';
      var data = '2';

    $.ajax({
        url: action,
        type: method,
        data: data

    }).done(function(data){
        $('.main').empty();
        $('.main').append(data);
    });

};

Now I want to make use of my data in a php-script (deleteEntry.php)

// SERVER SIDE CODE

<?php
    // VERBINDUNG //
    $connection = mysqli_connect('localhost', 'root', '', 'aufgabenplaner');
    // if (!$connection){
    //     die('Verbindung nicht möglich : ' . mysql_error());
    // }

    // SQL-ABFRAGE //
    $query = "DELETE FROM aufgaben WHERE job_nr =" ."DATA GOES HERE!!!";
    $result = mysqli_query( $connection, $query );

    include 'main-content.php';
?>

Where it says "DATA GOES HERE!!!" I want to make use of the data value, but I don't know how.