SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function midpoint (alias result) (children 1)
     ExpressionList (children 2)
      Literal UInt64_123
      Literal NULL
    Function toTypeName (alias type) (children 1)
     ExpressionList (children 1)
      Identifier result