public void UniqueTest()
        {
            TestData  TestData  = new TestData(gateway.Accessor);
            DbGateway dbGateway = new DbGateway(gateway.Accessor);

            gateway.CreateTable(typeof(User));

            User user = TestData.TestUser;

            dbGateway.Insert(user);

            try
            {
                dbGateway.Insert(user);
                Assert.Fail();
            }
            catch
            {
            }
        }