stmt.Parse(&Tag{})
		stmt.Schema.LookUpField("ID").Unique = true
		// postgers only allow unique constraint matching given keys
	}

	DB.Migrator().DropTable(&Blog{}, &Tag{}, "blog_tags", "locale_blog_tags", "shared_blog_tags")
	if err := DB.AutoMigrate(&Blog{}, &Tag{}); err != nil {
		t.Fatalf("Failed to auto migrate, got error: %v", err)
	}

	blog := Blog{
		Locale:  "ZH",
		Subject: "subject",
		Body:    "body",

		},
		Relation{
			Name: "SharedTags", Type: schema.Many2Many, Schema: "Blog", FieldSchema: "Tag",
			JoinTable: JoinTable{Name: "shared_blog_tags", Table: "shared_blog_tags"},
			References: []Reference{
				{"ID", "Blog", "BlogID", "shared_blog_tags", "", true},
				{"ID", "Tag", "TagID", "shared_blog_tags", "", false},
			},
		},
		Relation{
			Name: "LocaleTags", Type: schema.Many2Many, Schema: "Blog", FieldSchema: "Tag",