Re: New RDBMS implementation

Em Tue, 04 May 2004 01:54:40 +0000, Alfredo Novoa escreveu:

> And it is probable that they can not implement the Transrelational Model.

        After talking this with Nathan, I am not so sure... the issue seems to me more that he doesn't quite believe the thing. Nor do I can say to have quite understood it... someday I need to read those patents.

>>OTOH it is a complete
>>RAD environment.
>
> The frontend is not flexible enough for us

        Interesting, what do you need above and beyond what Dataphor provides or intends to provide?

> And we need [...] cheap server licenses

        Nothing could be cheaper than using PostgreSQL as a device, granted they will probably charge once they have their own thing.

> and preferabily a distributed DBMS
> architecture with many data cached in the desktop PCs, compressed and
> encrypted communications, etc.

        They do some client constraint enforcement... data cached on the client is an interesting concept, it is also a tall order.

>> Did you actually read the patents?
>
> Of course

        This 'of course' just proves how higher are your powers of concentration and comprehension than mine!

> but my data structures are rather different and they can be
> used in disk based DBMSs. Date mentioned that the Transrelational Model
> was adapted to be used with disk based DBMSs and I wonder if they used the
> same solution as me (modified B-Trees).

        So you're in touch with The Man... good.

> I also wonder if the modifications are enough to avoid problems with the
> patent if I want to distribute it in the US, Canada or Japan.
>
> Software patents are crazy.

        Agreed... had you the money, it would be interesting to get lawyers to clear up the path to you, or to arrange for a license with ReqTech -- but according to Nathan they're not quite responsive.

>> Are you keeping an eye in Portable.Net or Mono portability?
>
> No, I am keeping an eye in the Compact .Net framework. But I don't think I
> am using anything non portable.

        There are two concepts to 'portable' here... what is potentially portable, and what can run elsewhere now... Dataphor can't yet.

> The published LARL grammar has many mistakes, it is a toy language and
> some constructions are ugly IMO.

        I seem to remembered this was admitted by the authors themselves...

> start transaction and commit transaction are not required. Any language
> script is executed in the same transaction by default.

        So you implement that idea of the statement as the transaction... I haven't yet made my mind on it, but as long as one doesn't deal with a host language and a data sublanguage it really seems the thing to do.

        Now what if one needs a data sublanguage in a host language?

> The language is case insensitive and it does not have '_' characters
> inside the keywords. Like in SameTypeAs();

        Do you mean you forbid that, or just that you've gone Hungarian yourself? Bad or not so bad...

> It is possible to assign an expression to another expression:
>
> a join b := c minus d;

        Nice.

> It is possible to reference an expression in a foreign key definition
>
> var a relation { a integer }
> foreign key {a} references a join b;

        Nice.

> It has more builtin types like: numeric, date, timestamp, int32, int64,
> int8, etc.

        As long as you enable user defined types, possreps and the whole shebang...

> TABLE_DEE and TABLE_DUM are called Dee and Dum because they are not
> tables.

        :-)

> BTW what do you think about Tutorial D as a general purpose programming
> language?

        It was never meant to be one. The authors themselves have stated that, and that it would be interesting to see how would be a functional D...

> The most important problem is the IDE :(

        Yes, the big issue for me to experiment with Dataphor is that VisualStudio.Net is required.

> I knew almost nothing about the .Net framework in that moment, but now I
> think that .Net is the best option. The imperative parts of Tutorial D are
> very easy to implement with the .Net framework.

        Java would get you the portability .Net is yet only promising... I'm not a coder, but I gather Java is not significantly worse than .Net.

        Obviously there are other portable languages, like Common Lisp.

> I made a prototype for Win32 using Firebird as the backend but I dropped
> it because it was slow and some features were very hard to implement and
> because I have learned about the Transrelational Model.

        Win32 is suicide, no wonder MS has deprecated its use.

        If you really meant to use an existing SQL DBMS, PostgreSQL would be the way to go, perhaps. It was once relational (Ingres QUEL), and it has already been morphed from QUEL to SQL, so it should have yet the interfaces clean enough to go back.

> BTW I heared that programming languages have copyright in the US :(

        Know nothing about that... IANAL.

>> BTW, what about planned licensing, availability etc?
>
> A bit soon for that, but my associates would kill me if I publish all the
> code :)

        Perhaps they should learn about copy rights... publishing does not mean abdicating of any rights.

        There are quite some companies making big bucks by publishing code and then supporting it. Zope, the GNU toolchain, the GNU Ada compilers, Ghostscript all work like that.

> But it is a little crazy project. I can't promise anything. I will do only
> all I am able to do, but I am optimist and it is a very interesting job.

        I hope to include Dataphor in a technology evaluation for my employers later this year. Perhaps you will have something publishable by then?

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