SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function array (children 1)
     ExpressionList (children 1)
      Function concat (children 1)
       ExpressionList (children 2)
        Literal NULL
        Function arrayJoin (children 1)
         ExpressionList (children 1)
          Function array (children 1)
           ExpressionList