What is the bug?
Subquery aliasing doesn't work with ` characters.

How can one reproduce the bug?
Steps to reproduce the behavior:

1. Make a query for

SELECT `a`.`LOD - Fixed - 1 (copy 2)` AS `LOD - Fixed - 1 (copy 2)`
FROM (
  SELECT MIN(`Staples`.`Order Date`) AS `LOD - Fixed - 1 (copy 2)`
  FROM `staples` `Staples`
  GROUP BY `Staples`.`Customer Name`
) `a`
GROUP BY `LOD - Fixed - 1 (copy 2)`
ORDER BY `LOD - Fixed - 1 (copy 2)` ASC

2. See "ClassCastException"

What is the expected behavior?
Behaviour should match if the alias of the inner query is just a which is a valid result.

What is your host/environment?

• OpenSearch 1.3.1