var emptyUser User
	var err error
	// belongs to
	err = DB.Model(&emptyUser).Association("Company").Delete(&user1.Company)
	AssertEqual(t, err, gorm.ErrPrimaryKeyRequired)
	// has many
	err = DB.Model(&emptyUser).Association("Pets").Delete(&user1.Pets)
	AssertEqual(t, err, gorm.ErrPrimaryKeyRequired)
	// has one
	err = DB.Model(&emptyUser).Association("Account").Delete(&user1.Account)