@Override
    public Collection<DatabasePacket> execute() {
        // TODO consider what severity and error code to use
        PostgreSQLErrorResponsePacket packet = PostgreSQLErrorResponsePacket.newBuilder(PostgreSQLMessageSeverityLevel.ERROR, PostgreSQLVendorError.FEATURE_NOT_SUPPORTED,
                PostgreSQLVendorError.FEATURE_NOT_SUPPORTED.getReason()).build();
        return Collections.singleton(packet);
    }
@Test
    void assertExecute() {
        PostgreSQLUnsupportedCommandExecutor commandExecutor = new PostgreSQLUnsupportedCommandExecutor();
        Collection<DatabasePacket> actual = commandExecutor.execute();
        assertThat(actual.size(), is(1));
        assertThat(actual.iterator().next(), instanceOf(PostgreSQLErrorResponsePacket.class));
    }