SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function coalesce (alias x) (children 1)
     ExpressionList (children 2)
      Literal NULL
      Function toNullable (children 1)
       ExpressionList (children 1)
        Literal UInt64_2
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier x
