Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!news.swapon.de!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: Robert Klemme Newsgroups: comp.lang.java.programmer Subject: Re: what are java specsification? what are reference implementation? Date: Sat, 09 Aug 2014 12:29:29 +0200 Lines: 34 Message-ID: References: <678be024-b901-4567-ac9d-78eb4af4d5fc@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: individual.net D2gZmmiR0MbO0XkkqgxOeQEuULAlOHO3tFhN/PkRoeGYe/nvQ= Cancel-Lock: sha1:UuCOtvZKM8wMMA6FE+3mw71Xv78= User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 In-Reply-To: Xref: csiph.com comp.lang.java.programmer:29595 On 09.08.2014 03:37, Roedy Green wrote: > The idea was people without budget could use a free implementation, > and if the project were a roaring success, they could relatively > easily migrate to a more gold plated implementation. > > SQL is the granddaddy of this sort of thinking. The problem is the > spec is so loose, it is a major task to migrate to a different > engine.. They don't even use identical syntax for identical > functions, and there is no guarantee even basic functionality has to > be supported. > > It is time a new tighter spec. I don't think the spec is to blame. The issue is that implementations were around before the different versions of the spec and vendors chose compatibility to their older versions over compatibility to a recent standard of SQL. In some cases there is no way to provide both - standard and custom syntax at the same time (e.g. Oracle's data type DATE which is really a timestamp while in the standard it is really a date only). So, as always, having a good specification is one thing - the adherence of implementations to the spec is another. With commercial vendors there is usually a tendency to provide features that break or at least extend a standard to allow for vendor lock in. As you can see, in case of Oracle databases that works pretty well. Of course, users of those products would prefer more independence but they seem to have enough advantages of using a proprietary product to continue to do so. Cheers robert