SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function arrayStringConcat (children 1)
     ExpressionList (children 2)
      Function materialize (children 1)
       ExpressionList (children 1)
        Literal Array_[NULL, \'hello\', NULL, \'world\', NULL, \'xyz\', \'def\', NULL]
      Literal \';\'
