castopod/app/Database/Migrations/2021-02-23-100000_add_episode_id_to_notes.php

<?php

/**
 * Class AddEpisodeIdToNotes Adds episode_id field to activitypub_notes table in database
 *
 * @copyright  2020 Podlibre
 * @license    https://www.gnu.org/licenses/agpl-3.0.en.html AGPL3
 * @link       https://castopod.org/
 */

namespace App\Database\Migrations;

use CodeIgniter\Database\Migration;

class AddEpisodeIdToNotes extends Migration
{
    public function up(): void
    {
        $prefix = $this->db->getPrefix();

        $createQuery = <<<CODE_SAMPLE
            ALTER TABLE {$prefix}activitypub_notes
            ADD COLUMN `episode_id` INT UNSIGNED NULL AFTER `replies_count`,
            ADD FOREIGN KEY {$prefix}activitypub_notes_episode_id_foreign(episode_id) REFERENCES {$prefix}episodes(id) ON DELETE CASCADE;
        CODE_SAMPLE;
        $this->db->query($createQuery);
    }

    public function down(): void
    {
        $this->forge->dropForeignKey('activitypub_notes', 'activitypub_notes_episode_id_foreign',);
        $this->forge->dropColumn('activitypub_notes', 'episode_id');
    }
}