wallabag/app/DoctrineMigrations/Version20170511115400.php

<?php

namespace Application\Migrations;

use Doctrine\DBAL\Schema\Schema;
use Wallabag\CoreBundle\Doctrine\WallabagMigration;

/**
 * Added `headers` field in entry table.
 */
class Version20170511115400 extends WallabagMigration
{
    /**
     * @param Schema $schema
     */
    public function up(Schema $schema)
    {
        $entryTable = $schema->getTable($this->getTable('entry'));

        $this->skipIf($entryTable->hasColumn('headers'), 'It seems that you already played this migration.');

        $entryTable->addColumn('headers', 'text', [
            'notnull' => false,
        ]);
    }

    /**
     * @param Schema $schema
     */
    public function down(Schema $schema)
    {
        $entryTable = $schema->getTable($this->getTable('entry'));

        $this->skipIf(!$entryTable->hasColumn('headers'), 'It seems that you already played this migration.');

        $entryTable->dropColumn('headers');
    }
}