SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function uniqUpTo (children 2)
     ExpressionList (children 1)
      Function CAST (children 1)
       ExpressionList (children 2)
        Function unhex (children 1)
         ExpressionList (children 1)
          Literal \'00\'
        Literal \'AggregateFunction(uniqUpTo(5), Nullable(Nothing))\'
     ExpressionList (children 1)
      Literal UInt64_5
