switch ($this->connection->getDatabasePlatform()->getName()) {
case 'mysql':
+ $this->addSql('UPDATE ' . $this->getTable('entry') . ' SET reading_time = 0 WHERE reading_time IS NULL;');
$this->addSql('ALTER TABLE ' . $this->getTable('entry') . ' CHANGE reading_time reading_time INT(11) NOT NULL;');
break;
case 'postgresql':