public function testTimestampNotUpdatedIfNotModified()
 {
     $this->loadData('articles');
     $article = Article::selectOne($this->getConn())->execute();
     $created = $article->created_at;
     $updated = $article->updated_at;
     $article->update();
     $this->assertSame($created, $article->created_at);
     $this->assertSame($updated, $article->updated_at);
 }