I want to write a small application that requires a database but instead of writing my own flat file database inside the application I'd prefer to use a module that would take care of the database related stuff like finding and returning the correct transaction, adding a transaction to the database and all that. That would leave me more time to write my application.

I'm not really interested in buying a full database program like S-Base to develop my application in - more like a module that I can talk to (SQL for example) and develop my program in C/C++, Basic or whatever.


[Edited by 172 at 13:14, 28/10/2000]

Well i tried to check this pages but there noone talk about S.Q.L. .... but thank you either and w will see....

Perhaps it's worth emailing the authors and asking them. It would seem to me that there are two core header files that need to be exported as SWI calls (tbase.h and database.h I think). The rest appear to be internal data structures and the like. In general writing modules in C isn't that difficult - assuming they're using Acorn C of course.

Of course then module then has to cope with multiple databases, but from reading the docs is would appear to be able to do this already. In this case all the application needs is a handle to the database which could be passed in each SWI call.

It should be ready in a couple of days, when I get started of course.

SQL would be an optional extra or could even be written as a layer on top of this module? Probably better to have it relational first though?

do you know of any good books about writing a database program? I'm starting to see spare time in the near future and I'm still interested in getting my hands on a database program for RISC OS. I might use the TBaseLib but I also write it from scratch.

Perhaps not quite directly useful, but if Gulli if you look into how Delphi (on the PC) addresses the abstract BDE (database engine) it might give you some ideas. I've been toying with the idea of creating a db module myself (not a line of code yet though!).

The sort of abstraction they use allow the user to address flatfiles or xBase (dBase, FoxBase) files as if they're SQL databases (you can even use SQL Selects and other commands on them !) or even apply a simple record based model to complex SQL database servers (like Interbase, Oracle or MS SQL Server). So whatever model suits you you can use (irrespective of the underlying database).

Very often you can just switch from a dbase style database (with SQL access) to a multiuser large scale database (like Oracle) with little or no additional programming.

Interestingly Borlands Interbase server has gone Open source !!! (I think its written in C++ so given the right compiler it could perhaps be ported to RISC OS (it already runs on Windows and Linux)).

Just a few ideas to mull over......

S.Q.L. (SEQUEL) was made by IBM in the '70. Its long name was Structured English Query Language (actually Structured Query Language).

S.Q.L. is a standard langauge for use datas recorded in relationals databases.

It was made from "relational databases" experiences and it is very easy to learn than many others query langauges.

Actually S.Q.L. is grow a lot then the first project and it is the most popular query language of the world (see My SQL, PostgreSQL, M.S. SQL Server, Oracle and more).<br><br>[Edited by Paolo Zaino at 23:06, 21/11/2001]

[Edited by Paolo Zaino at 23:07, 21/11/2001]

I am italian so i know italian books and i should make a search for know english versions of them...

Anyway i don't think that exsist "the complete manual for build a D.B.M.S." or maybe not...

I understand Gulli's need for a database module and why TBase is not suitable in this case. However on downloading TBase I immediately thought "this would make a really good module".

Perhaps it's worth emailing the authors and asking them. It would seem to me that there are two core header files that need to be exported as SWI calls (tbase.h and database.h I think). The rest appear to be internal data structures and the like. In general writing modules in C isn't that difficult - assuming they're using Acorn C of course.

For those with a few quiet minutes:
the database management system (DBMS) is often confused with the database itself. A database lives in one or more data files, and is relatively trivial to knock up. the DBMS sorts out file access, updates, searches and that kind of thing. if you have different kinds of data, you will need to split these up somehow and the dbms then handles complex queries for you - eg an sql interpreter and transaction logs. The heavyweight answer is the Relational dbms, but this a) is processor-intensive, b) needs much expertise to design-in and maintain data integrity (using primary keys and stuff), and c) is pretty complex in itself.

riscos is a lousy os for multi-user databases because it doesn't easily handle multiple user tasks. if that's important down the line, you might do better to run a web connection to a linux box running mysql or something, but i don't think there will be any relevant swi's ;(

<blockquote>
Anyway i don't think that exsist "the complete manual for build a D.B.M.S." or maybe not...</blockquote>

I don't want a complete manual anyway, something that explains the construction of the data storing and retrieving algorithms would be far more interesting

Cheers,
Guy

I agree with Guy, to make a program for build Databases in S.Q.L. language is very easy, you need only to have a S.Q.L. internals book and you will make it faster (well i hope lol ).

the problem is the DBMS (the software who manage your databases).

As i always said in other parts of this forum:

a) RISC OS have not protected memory system so your datas will never have an high security level.

b) RISC OS have not multithread programming stuffs so it will be very hard to make a software who manage the D.B. connections by applications and users.

c) RISC OS is still not 32 bits , that means that anyD.B. will not be fast managed as a 32 BITS D.B.

d) Database world is joined with fast data storage world and till now i didn't see a Fast data storage on any RISC PCs; my RiscPC have Powertec 32 bits Ultra DMA SCSI card and it works at max 4 , 4.5 Mbytes for second....

what was possible to do on RISC OS is already done... (some desktop D.B. softwares just for study the D.B. world.)

BUT!!!! I STILL SAY THAT A.R.M. Processors can be very good in a professional kinds, i want remember that the new Strong A.R.M. is faster than a PENTIUM IV so please there is someone that want let this processors make their wonderfull work? (please someone say yes! )

[Edited by Paolo Zaino at 14:04, 25/11/2001]

Sorry if i didn't answer to your message Gunnlaugur, but my work give all my time actually, i try now if you accept my apollogize...

No worries Paolo, I have had much less time than I originally thought so I wouldn't have done anything about it anyway

I am italian so i know italian books and i should make a search for know english versions of them...

That would be good, my Italian isn't exactly worth mentioning

Anyway i don't think that exsist "the complete manual for build a D.B.M.S." or maybe not...

I don't want a complete manual anyway, something that explains the construction of the data storing and retrieving algorithms would be far more interesting

do you know of any good books about writing a database program? I'm starting to see spare time in the near future and I'm still interested in getting my hands on a database program for RISC OS. I might use the TBaseLib but I also write it from scratch.

Perhaps not quite directly useful, but if Gulli if you look into how Delphi (on the PC) addresses the abstract BDE (database engine) it might give you some ideas. I've been toying with the idea of creating a db module myself (not a line of code yet though!).

The sort of abstraction they use allow the user to address flatfiles or xBase (dBase, FoxBase) files as if they're SQL databases (you can even use SQL Selects and other commands on them !) or even apply a simple record based model to complex SQL database servers (like Interbase, Oracle or MS SQL Server). So whatever model suits you you can use (irrespective of the underlying database).

Very often you can just switch from a dbase style database (with SQL access) to a multiuser large scale database (like Oracle) with little or no additional programming.

That's something to think about. It might be a way to achive what I need.
If you do start making a db module please send me an e-mail as I may have a couple of ideas for what might be needed from that module and possibly be able to contribute something.

Interestingly Borlands Interbase server has gone Open source !!! (I think its written in C++ so given the right compiler it could perhaps be ported to RISC OS (it already runs on Windows and Linux)).

Yet again that dreaded C++ compiler problem! Anyone out there reading this?

[Edited by Gulli at 10:25, 10/5/2001]

Problem (I may be misunderstanding you completely): If I was thinking of writing an application that could store it's entire data in memory I wouldn't really need the database module!

Also I would like to be able to assign the primary key myself (not use autonumber)

I've got no idea what SQL is, but I expect just about anything will be possible.

Hmm, that's a bit discomforting to hear from someone who's about to write a database!

All the module would know would be the database reference (as a pointer to it in memory), an object reference (as a number which gets increased as each new object is added),

Problem (I may be misunderstanding you completely): If I was thinking of writing an application that could store it's entire data in memory I wouldn't really need the database module! Also I would like to be able to assign the primary key myself (not use autonumber)

field number (auto-increasing again), the length of the field (pre-defined or varying), and the actual data (just as a block of memory). Things like encryption and security might be supported at some stage, but for the first version I'll just leave it to the programmer.

I could knock up the reading code in a few minutes, but the main problem would be the memory management (keeping all internal pointers up to date). If it's urgently needed I could get it done and give you a copy (complete with source) by the end of the week (I think). If not, it really just depends on how I feel at the time

No, I'm not in any hurry. I've just been thinking about writing a program that would require a simple database of some sort but I don't see that happening in the next three or four months.

172

I could knock up the reading code in a few minutes, but the main problem would be the memory management (keeping all internal pointers up to date). If it's urgently needed I could get it done and give you a copy (complete with source) by the end of the week (I think). If not, it really just depends on how I feel at the time

But for the server side? eheheh that's is the most big problem... if we try to implement it people will love to use it with (for example) PHP language for build internet sites, or in a LAN for share databases or manage informations etc... (well i'm still studing this so for now is better to no dream too far for me!) ehehehe

What I'm looking for is a database program/module that I can talk to with SWIs, not compiling it inside my own program. Something I could either include in a distribution or advice people on where to get it. I know this could be a bit risky since RISC OS software quite often seems to disappear as soon as it's released but I think that with a few applications relying on it, it's more likely to stay there.

Paolo:
I'm VERY interested in participating in making an SQL database for RISC OS but at the moment I hardly have enough time for both work and school so I would probably not be of much use until next summer.
If, however, you start writing one I'll be more than happy to take part in it. I hardly know anything about database programming, which is why I was looking for one in the first place, but one can always learn one more thing

Maybe an SQL Database can be built using the Tbase lib? Tbase really looks fast on my SA RiscPC.

172


[Edited by 172 at 12:19, 11/11/2000]

I was hoping someone has written a module that anyone could use - for a price of course. In my opinion this could seriously boost application development for RISC OS. I'd do it myself if I just knew how or had the time to learn to. Maybe I'll have time next July though