SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function substring (children 1)
     ExpressionList (children 3)
      Function CAST (children 1)
       ExpressionList (children 2)
        Literal \'abcdefgh\'
        Literal \'FixedString(8)\'
      Literal Int64_-2
      Literal Int64_-2