From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.3 required=5.0 tests=BAYES_00, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,229ea0001655d6a2 X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news3.google.com!proxad.net!news.in2p3.fr!in2p3.fr!news.ecp.fr!news2.arglkargh.de!noris.net!newsfeed.arcor.de!newsspool1.arcor-online.net!news.arcor.de.POSTED!not-for-mail From: "Dmitry A. Kazakov" Subject: Re: Generic Package Newsgroups: comp.lang.ada User-Agent: 40tude_Dialog/2.0.15.1 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Reply-To: mailbox@dmitry-kazakov.de Organization: cbb software GmbH References: <1177539306.952515.222940@s33g2000prh.googlegroups.com> <1177601484.444701.171560@r35g2000prh.googlegroups.com> <1177672290.8055.6.camel@localhost> Date: Sat, 28 Apr 2007 09:36:00 +0200 Message-ID: <1bd15h5ycjysm.pt7okr08mdzx.dlg@40tude.net> NNTP-Posting-Date: 28 Apr 2007 09:35:44 CEST NNTP-Posting-Host: 007fd78f.newsspool3.arcor-online.net X-Trace: DXC=i<9GY\af_Y5=FQB?mjjV50McF=Q^Z^V384Fo<]lROoR1Fl8W>\BH3Y2QFKXiB`9j^:DNcfSJ;bb[5IRnRBaCdd`aT1dPB0a?47lh_]3l0a? X-Complaints-To: usenet-abuse@arcor.de Xref: g2news1.google.com comp.lang.ada:15375 Date: 2007-04-28T09:35:44+02:00 List-Id: On Fri, 27 Apr 2007 22:16:35 +0100, Simon Wright wrote: > "Dmitry A. Kazakov" writes: > >> On Fri, 27 Apr 2007 20:44:13 +0100, Simon Wright wrote: >> >>> "Dmitry A. Kazakov" writes: >>> >>>> On Fri, 27 Apr 2007 13:11:30 +0200, Georg Bauhaus wrote: >>> >>>>> Any real table in an existing computer has a "natural" >>>>> ordering suitable for iterating an operation for all >>>>> elements: data in a real computer can be uniquely identified. >>>> >>>> No this is wrong even on a real computer. The DB engine could >>>> shuffle the rows asynchronously to your application. There could be >>>> other applications playing with the table. The table might spread >>>> over memories of several computers and different levels cashes. You >>>> have to bring transactions, replications and other synchronizing >>>> stuff to make any sense out of "natural order." >>> >>> Just using ordered containers is hardly going to stop you needing to >>> deal with locking! >> >> In some sense it would. Provided it existed unconditionally, you would not >> need to lock anything. Because otherwise any relevant change would destroy >> the order in contradiction to the premise. Obviously you don't need to lock >> if possible changes wouldn't affect the order. > > I can't imagine any sense in which it could. Perhaps you're thinking > of special hardware that could have these properties? Or just "per magic," like priority ceiling locking. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de