Mercurial > urweb

view caching-tests/test.ur @ 2237:e79ef5792c8b

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fix bug in redundancy checking and use finer formula for UPDATE statements.
author Ziv Scully <ziv@mit.edu>
date Sun, 05 Jul 2015 23:57:28 -0700
parents fab8c1f131a5
children 7f92d70a326e
line wrap: on
line source
table tab : {Id : int, Val : int} PRIMARY KEY Id

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 =
     dml (UPDATE tab
          SET Val = 42
          WHERE Id = {[id]} OR Id = {[id - 1]} OR Id = {[id + 1]});
    return <xml><body>
      Changed {[id]}!
    </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]} OR Id = {[id + 1]})); *)
(*     return <xml><body> *)
(*       {case res of *)
(*            None => <xml>Initialized {[id]}!</xml> *)
(*          | Some row => <xml>Incremented {[id]}!</xml>} *)
(*     </body></xml> *)