@Test
  public void testSubQueryInFrom() throws ParseException {
    parse("select * \n" +
        "\n" +
        "from (select * \n" +
        "\n" +
        "      from `src/_/cbo` b \n" +
        "\n" +
        "      where exists \n" +
        "\n" +
        "          (select a.key \n" +
        "\n" +
        "          from `src/_/cbo` a \n" +
        "\n" +
        "          where b.value = a.value  and a.key = b.key and a.value > 'val_9')\n" +
        "\n" +
        "     ) a\n" +
        "\n");
  }
Parser tests special character in table names.
parser/src/test/org/apache/hadoop/hive/ql/parse/TestSpecialCharacterInTableNames.java