【PHP・Symfony + EC-CUBE】テーブル作成時の外部キー制約違反の解決

<?php

namespace DoctrineMigrations;

use Doctrine\DBAL\Migrations\AbstractMigration;
use Doctrine\DBAL\Schema\Schema;


/**
 * Auto-generated Migration: Please modify to your needs!
 */
 class Version20210101000000 extends AbstractMigration
 {
  /**
  * @param Schema $schema
  */
  public function up(Schema $schema)
  {
    // this up() migration is auto-generated, please modify it to your needs
    $this->addSql("CREATE TABLE book_categories (id SMALLINT NOT NULL, name LONGTEXT NOT NULL, rank SMALLINT NOT NULL, PRIMARY KEY(id)) DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ENGINE = InnoDB ;");  // book_categoriesテーブルの作成
    $this->addSql("INSERT INTO book_categories (id, name, rank) VALUES (1, '図鑑', 1);"); // book_categoriesテーブルにデータ挿入
    $this->addSql("INSERT INTO book_categories (id, name, rank) VALUES (2, '雑誌', 2);"); // book_categoriesテーブルにデータ挿入

    $this->addSql("ALTER TABLE books ADD book_category_id SMALLINT NOT NULL ;"); // booksテーブルにbook_category_idカラムを追加
    $this->addSql("ALTER TABLE books ADD CONSTRAINT FK_98604EA3AAAA0A00 FOREIGN KEY (book_category_id) REFERENCES mtb_lending_content (id);"); // 外部キー制約の使用
    $this->addSql("CREATE INDEX IDX_98604EA3AAAA0A00 ON books (book_category_id);"); // インデックスの作成
  }


 /**
  * @param Schema $schema
  */
  public function down(Schema $schema)
  {
    // this down() migration is auto-generated, please modify it to your needs

    $this->addSql("ALTER TABLE books DROP FOREIGN KEY `FK_98604EA3AAAA0A00`;");
    $this->addSql("ALTER TABLE books DROP COLUMN book_category_id;");
    $this->addSql("DROP TABLE IF EXISTS `book_categories`;");
  }
 }