Mercurial > urweb

table foo01 : {Id : int, Bar : string} PRIMARY KEY Id
table foo10 : {Id : int, Bar : string} PRIMARY KEY Id
table tab : {Id : int, Val : int} PRIMARY KEY Id

fun cache01 () =
    res <- oneOrNoRows (SELECT foo01.Bar FROM foo01 WHERE foo01.Id = 43);
    return <xml><body>
      Reading 1.
      {case res of
           None => <xml>?</xml>
         | Some row => <xml>{[row.Foo01.Bar]}</xml>}
    </body></xml>

(* fun cache10 () = *)
(*     res <- queryX (SELECT foo10.Bar FROM foo10 WHERE foo10.Id = 42) *)
(*                   (fn row => <xml>{[row.Foo10.Bar]}</xml>); *)
(*     return <xml><body> *)
(*       Reading 2. *)
(*       {res} *)
(*     </body></xml> *)

(* fun cache11 () = *)
(*     res <- oneOrNoRows (SELECT foo01.Bar FROM foo01 WHERE foo01.Id = 42); *)
(*     bla <- oneOrNoRows (SELECT foo10.Bar FROM foo10 WHERE foo10.Id = 42); *)
(*     return <xml><body> *)
(*       Reading 1 and 2. *)
(*       {case res of *)
(*            None => <xml>?</xml> *)
(*          | Some row => <xml>{[row.Foo01.Bar]}</xml>} *)
(*       {case bla of *)
(*            None => <xml>?</xml> *)
(*          | Some row => <xml>{[row.Foo10.Bar]}</xml>} *)
(*     </body></xml> *)

fun flush01 () =
    dml (INSERT INTO foo01 (Id, Bar) VALUES (42, "baz01"));
    (* dml (UPDATE foo01 SET Bar = "baz01" WHERE Id = 42); *)
    return <xml><body>
      Flushed 1!
    </body></xml>

(* fun flush10 () = *)
(*     dml (UPDATE foo10 SET Bar = "baz10" WHERE Id = 42); *)
(*     return <xml><body> *)
(*       Flushed 2! *)
(*     </body></xml> *)

(* fun flush11 () = *)
(*     dml (UPDATE foo01 SET Bar = "baz11" WHERE Id = 42); *)
(*     dml (UPDATE foo10 SET Bar = "baz11" WHERE Id = 42); *)
(*     return <xml><body> *)
(*       Flushed 1 and 2! *)
(*     </body></xml> *)

fun cache id =
    res <- oneOrNoRows (SELECT tab.Val FROM tab WHERE tab.Id = {[id]});
    return <xml><body>
      Reading {[id]}.
      {case res of
           None => <xml>?</xml>
         | Some row => <xml>{[row.Tab.Val]}</xml>}
    </body></xml>

fun flush id =
    res <- oneOrNoRows (SELECT tab.Val FROM tab WHERE tab.Id = {[id]});
    (case res of
         None => dml (INSERT INTO tab (Id, Val) VALUES ({[id]}, 0))
       | Some row => dml (UPDATE tab SET Val = {[row.Tab.Val + 1]} WHERE Id = {[id]}));
    return <xml><body>
      (* Flushed {[id]}! *)
      {case res of
           None => <xml>Initialized {[id]}!</xml>
         | Some row => <xml>Incremented {[id]}!</xml>}
    </body></xml>
author	Ziv Scully <ziv@mit.edu>
date	Thu, 11 Dec 2014 02:05:41 -0500
parents	278e10629ba1
children	6262dabc08d6