<?php

use yii\db\Migration;

/**
 * Class m180613_140138_alter_table_book
 */
class m180613_140138_alter_table_book extends Migration
{
    /**
     * {@inheritdoc}
     */
    public function safeUp()
    {
        $this->addColumn('book', 'alias_id', $this->integer());
        
        $this->addForeignKey('book_alias_fk',
                            'book',
                            'alias_id',
                            'alias',
                            'id',
                            'CASCADE',
                            'CASCADE');
    }

    /**
     * {@inheritdoc}
     */
    public function safeDown()
    {
        $this->dropForeignKey('book_alias_fk', 'book');
        $this->dropColumn('book', 'alias_id');
    }
    
}