<?php

class OBUpdate20200706 extends OBUpdate {

  public function items () {
    $updates   = array();
    $updates[] = "CASCADE user updates to client_storage table. Clean out any non-existing users first.";
    return $updates;
  }

  public function run () {
    $this->db->query('START TRANSACTION;');

    // CASCADE user updates to client_storage table. Clean out any non-existing users first.
    $this->db->query('DELETE FROM `client_storage` WHERE `user_id` NOT IN (SELECT `id` FROM `users`);');
    $this->db->query('ALTER TABLE `client_storage` ADD FOREIGN KEY (`user_id`) REFERENCES `users`(`id`) ON DELETE CASCADE ON UPDATE CASCADE;');

    $this->db->query('COMMIT;');
    if ($this->db->error()) return false;

    return true;
  }
}