if !compareTags(blog.SharedTags, []string{"tag1", "tag2", "tag3"}) {
		t.Fatalf("Blog should has three tags after Append")
	}

	if DB.Model(&blog).Association("SharedTags").Count() != 3 {
		t.Fatalf("Blog should has three tags after Append")
	}

	if DB.Model(&blog2).Association("SharedTags").Count() != 3 {
		t.Fatalf("Blog should has three tags after Append")
	}

	var tags []Tag