psuedo code for crud operations

<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') {

    // send with $_POST['action'] a variable called ID
    if ($_POST['action'] === 'delete'){
        delete record where id= $_POST['id'];
    }

    if ($_POST['action'] === 'create'){
        create record with $_POST['fields'];
    }

    if ($_POST['action'] === 'update'){
        update record where id= $_POST['id'];
    }

    if ($_POST['action'] === 'read'){
        select record where id= $_POST['id'];
    }
}