Ada and Database

Ada and Database

[OPERA]

Happy new year !

I have a some "naive" questions regarding Ada and data bases (in SQL) :
1 - How can I implement a SQL data base in an Ada program developped
with
GNAT ? I mean is there some free package implementing a data base engine
in Ada that can directly understand a request in SQL something like :
    SQL_request(" SELECT ... FROM ....");
2 - More generaly, but tell me if I'm wrong, I suppose that it would be
usefull to extend the Ada langage with some data base facilities, a bit
like what has been done for tasking : a clear syntax directly
understandable at upper level and consistent with the rest of the
langage, and an implementation depending on what exists on the target :
if a good database engine already exists, then simply creates a binding
(like the binding bewteen Ada tasks and some OS thread) or if nothing
exists use the one provided by the compiler (like GNAT under Ms-DOS)...

Thanks for your response.

Re: Ada and Database

[Larry Kilgallen]

In article <3A520C8A.4BC39537@edf.fr>, OPERA <vincent.diemunsch@edf.fr> writes:

> GNAT ? I mean is there some free package implementing a data base engine
> in Ada that can directly understand a request in SQL something like :
>     SQL_request(" SELECT ... FROM ....");
> 2 - More generaly, but tell me if I'm wrong, I suppose that it would be
> usefull to extend the Ada langage with some data base facilities, a bit
> like what has been done for tasking : a clear syntax directly
> understandable at upper level and consistent with the rest of the
> langage, and an implementation depending on what exists on the target :
> if a good database engine already exists, then simply creates a binding
> (like the binding bewteen Ada tasks and some OS thread) or if nothing
> exists use the one provided by the compiler (like GNAT under Ms-DOS)...

I wouldn't mind a database interface, but I don't want your SQL stuff,
my preference is Codasyl.

For tasking, such religious issues do not exist, and implementations
of Ada must coerce the environment into supporting the Ada model.
It is unlikely that Ada has anything grand to offer the database
community, so binding to existing standards is better.

Re: Ada and Database

[Juergen Pfeifer]

> I have a some "naive" questions regarding Ada and data bases (in SQL) :
> 1 - How can I implement a SQL data base in an Ada program developped
> with
> GNAT ? I mean is there some free package implementing a data base engine
> in Ada that can directly understand a request in SQL something like :
>     SQL_request(" SELECT ... FROM ....");
> 2 - More generaly, but tell me if I'm wrong, I suppose that it would be
> usefull to extend the Ada langage with some data base facilities, a bit
> like what has been done for tasking : a clear syntax directly
> understandable at upper level and consistent with the rest of the
> langage, and an implementation depending on what exists on the target :
> if a good database engine already exists, then simply creates a binding
> (like the binding bewteen Ada tasks and some OS thread) or if nothing
> exists use the one provided by the compiler (like GNAT under Ms-DOS)...
>
The ISO92 Standard for SQL clearly defines some of these interfaces to
specific languages, especially to Ada (Ada83 in mind).

One of these interfaces is the "Command Level Interface" (CLI) which has
been added to the standard after 1992 (if I remember correctly around 1994
or 1995). This CLI was heavily influenced by Microsofts ODBC and
most implementations of this interface are actually ODBC implementations.

Another interface is embedded SQL (which is part of the original 1992
standard).
Here the idea is to embed the SQL language into various host languages (Ada
is one of them) and let a preprocessor translate this embedded statements
into
some DB specific interface calls.

A further interface is so called "SQL Module Language" and there has been
an associated ISO Standard "SameDL" dealing with the integration of this
approach and Ada83. This was for sure the most sophisticated approach and
therefore there virtually was no relevant implementation (too heavy stuff).
"SameDL" has expired and probably there will be no successor dealing
with Ada95.

There exist of course proprietary call level APIs for various databases
(OCI for Oracle, libpq for PostgreSQL etc.) and on the WEB you can find
bindings to these APIs. But that's rather lowlevel and non-portable stuff.
Most database vendors today don't provide embedded SQL preprocessors
for Ada, I guess due to low commercial interest in such products.

Just a few weeks ago a free software project codenamed GNADE has
started (GNu Ada Database Environment) which tries to implement some
of the standard APIs for use with GNAT. It is in a very early prototyping
stage and not really usable at the moment. But maybe you want to monitor
the efforts.

Please have a look at
    http://www.snafu.de/~boavista/gnade.html or
    http://www.familiepfeifer.de/software/GNADE.html
for some partial efforts. If you feel you can contribute, please contact me
by Email.

Cheers
J�rgen

Re: Ada and Database

[Mario Amado Alves]

On Tue, 2 Jan 2001, OPERA wrote:
> ... is there some free package implementing a data base engine in Ada
> that can directly understand a request in SQL something like :
>     SQL_request(" SELECT ... FROM ....");

A free binding to Postgres exists at

  http://lexis.di.fct.unl.pt/ADaLIB/db_resources.htm

There is also a binding to MySQL, I think (cf. AdaPower).

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|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Preben Randhol]

On Wed, 3 Jan 2001 15:19:28 +0000 (WET), Mario Amado Alves wrote:
>On Tue, 2 Jan 2001, OPERA wrote:
>> ... is there some free package implementing a data base engine in Ada
>> that can directly understand a request in SQL something like :
>>     SQL_request(" SELECT ... FROM ....");
>
>A free binding to Postgres exists at
>
>  http://lexis.di.fct.unl.pt/ADaLIB/db_resources.htm

The requested URL /ADaLIB/pg2.tgz was not found on this server.

As I recall last time I checked this, the license was not free in the
sense that it is compatible with the GPL. But I don't know if that has
changed.

-- 
Preben Randhol ---------------- http://www.pvv.org/~randhol/ --
iMy favorite editor is Emacs!<ESC>bcwVim<ESC>
                                         -- vim best-editor.txt

Re: Ada and Database

[Robert Dewar]

In article
<slrn958mre.7q6.randhol+abuse@kiuk0156.chembio.ntnu.no>,
  randhol+abuse@pvv.org (Preben Randhol) wrote:
> As I recall last time I checked this, the license was not
free in the
> sense that it is compatible with the GPL. But I don't know if
that has
> changed.


Why should GPL compatibility be an issue for runtime stuff?


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Re: Ada and Database

[Preben Randhol]

On Thu, 04 Jan 2001 14:43:58 GMT, Robert Dewar wrote:
>Why should GPL compatibility be an issue for runtime stuff?

Because the license here require that you advertice the binding as far
as I recall.

An alternative Postgresql binding can be found here: 

   http://www.infres.enst.fr/ANC/

-- 
Preben Randhol ---------------- http://www.pvv.org/~randhol/ --
iMy favorite editor is Emacs!<ESC>bcwVim<ESC>
                                         -- vim best-editor.txt

Re: Ada and Database

[Florian Weimer]

randhol+abuse@pvv.org (Preben Randhol) writes:

[ADaLIB]

> As I recall last time I checked this, the license was not free in the
> sense that it is compatible with the GPL. But I don't know if that has
> changed.

The license isn't compatible with the Debian Free Software Guidelines
either.  The notification requirement is particularly obnoxious.

Re: Ada and Database

[Mario Amado Alves]

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> [ADaLIB]
> 
> The license isn't compatible with the Debian Free Software Guidelines
> either.

URL?

> The notification requirement is particularly obnoxious.

Ouch!

The idea here is to collect usage metrics to help quantify the Adªlib
software process: I could not think of any other way to do this.
Suggestions? There is much talk of (personal) software process, but no
practice. The only way to evaluate software engineering issues is
experimentally, and for that we need data. But if it turns out that a
notification requirement is really that much offensive I will drop it.

Thanks.

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
|A|M|A|D|O|DepartmentoDeInformaticaFCT/UNL 2825-114 Caparica 351+212958536
|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Florian Weimer]

Mario Amado Alves <maa@di.fct.unl.pt> writes:

> > [ADaLIB]
> > 
> > The license isn't compatible with the Debian Free Software Guidelines
> > either.
> 
> URL?

http://www.debian.org/social_contract#guidelines

> > The notification requirement is particularly obnoxious.

> The idea here is to collect usage metrics to help quantify the Ad�lib
> software process: I could not think of any other way to do this.
> Suggestions?

Hmm.  Don't try to make it a formal requirement, make it suggestion.

The restriction to 'good software' is questionable, too...

Re: Ada and Database

[Mario Amado Alves]

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> [Adªlib]
> > > The notification requirement is particularly obnoxious.
> > The idea here is to collect usage metrics to help quantify the Adªlib
> > software process: I could not think of any other way to do this.
> > Suggestions?
> Hmm.  Don't try to make it a formal requirement, make it suggestion.

Yes, perhaps I should change 'must' to 'should'.

> The restriction to 'good software' is questionable, too...

Yes, it is. Ah!, l'engagement...

Thanks for all the nice suggestions. I will sleep on it for a few weeks.

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
|A|M|A|D|O|DepartmentoDeInformaticaFCT/UNL 2825-114 Caparica 351+212958536
|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Mario Amado Alves]

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> >A free binding to Postgres exists at
> >
> >  http://lexis.di.fct.unl.pt/ADaLIB/db_resources.htm
> 
> The requested URL /ADaLIB/pg2.tgz was not found on this server.

Fixed. Thanks for the warning. Non-documents in Adªlib are liable to be
unavailable at times.

> As I recall last time I checked this, the license was not free in the
> sense that it is compatible with the GPL. But I don't know if that has
> changed.

I think it is compatible. Adªlib is essentially open source. In fact I
think Adªlib is more free than GPL. Adªlib Conditions of Use are very
simple and *short*. Some of us can only understand _short_ legal texts,
because we become very sleepy after the first ten lines ;-) I keep looking 
for an understandable ten-line digest of GPL and "open source".

Thanks.

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
|A|M|A|D|O|DepartmentoDeInformaticaFCT/UNL 2825-114 Caparica 351+212958536
|A|L|V|E|S|                                                  fax 212948541
| | | | | |                 maa@di.fct.unl.pt                FCT 212948300

Re: Ada and Database

[Robert Dewar]

In article
<Pine.LNX.4.10.10101051416490.27577-100000@lexis.di.fct.unl.pt>

> Some of us can only understand _short_ legal texts,
> because we become very sleepy after the first ten lines ;-)

I cannot tell you how many court cases wallow in chaos caused
by non-lawyers thinking things like this, and writing down
what they think are simple straight-forward agreements that
turn out to be anything but.


> I keep looking for an understandable ten-line digest of GPL
> and "open source".

You will not find one, any ten line digest of a license
agreement is going to be full of confusion, misleading
implications, and errors.

I am sure there are people who would like to find a 4 page
booklet clearly describing all of Ada.

If you don't clearly understand the GPL, how can you possibly
make the judgment that your license (which I have not read)
is compatible with the GPL?


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Re: Ada and Database

[Larry Kilgallen]

In article <937kvb$tc3$1@nnrp1.deja.com>, Robert Dewar <robert_dewar@my-deja.com> writes:

> If you don't clearly understand the GPL, how can you possibly
> make the judgment that your license (which I have not read)
> is compatible with the GPL?

To quote Bill Hancock:

	If a vendor says "compatible" they mean "different".
	If they meant "same" they would say "same".

Re: Ada and Database

[Robert Dewar]

In article <0dDf6NA7DYK4@eisner.decus.org>,
  Kilgallen@eisner.decus.org.nospam (Larry Kilgallen) wrote:
> In article <937kvb$tc3$1@nnrp1.deja.com>, Robert Dewar
<robert_dewar@my-deja.com> writes:
>
> > If you don't clearly understand the GPL, how can you
possibly
> > make the judgment that your license (which I have not read)
> > is compatible with the GPL?
>
> To quote Bill Hancock:
>
> 	If a vendor says "compatible" they mean "different".
> 	If they meant "same" they would say "same".

Well that's amusing, but really a bit obfuscatory in this
context. The legal concept of a license being compatible
with the GPL is an important one. The GPL allows you limited
rights to distribute. You can only mix GPL'ed code with other
code that is under a compatible license, where compatibility
is defined as a license that does not "impose any further
restrictions". Yes the GPL is compatible with itself in
this sense, but it is also compatible with any less restrictive
license.


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Re: Ada and Database

[Mario Amado Alves]

On Sat, 6 Jan 2001, Robert Dewar wrote:
> compatibility is defined as a license that does not "impose any further
> restrictions". Yes the GPL is compatible with itself in this sense, but
> it is also compatible with any less restrictive license.

Hmmm... So a license slightly more restrictive than GPL may be compatible
with GPL.

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
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|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Robert Dewar]

In article
<Pine.LNX.4.10.10101081452530.27577-100000@lexis.di.fct.unl.pt>
,
  comp.lang.ada@ada.eu.org wrote:
> On Sat, 6 Jan 2001, Robert Dewar wrote:
> > compatibility is defined as a license that does not "impose
any further
> > restrictions". Yes the GPL is compatible with itself in
this sense, but
> > it is also compatible with any less restrictive license.
>
> Hmmm... So a license slightly more restrictive than GPL may
be compatible
> with GPL.

No, that's false (perhaps there is a language problem, but
the sentence you quote from me is quite incompatible with
your conclusion).


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Re: Ada and Database

[Mario Amado Alves]

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--...compatibility is defined as a license that does not "impose any
further restrictions". Yes the GPL is compatible with itself in this sense,
but it is also compatible with any less restrictive license. (Dewar)

--Hmmm... So a license slightly more restrictive than GPL may be
compatible with GPL.
 
--No, that's false (perhaps there is a language problem, but the
sentence you quote from me is quite incompatible with your conclusion).
(Dewar)

--You are probably right. What I meant is an _open_source_ license (e.g.
Adªlib's) slightly more restrictive than GPL may be compatible with GPL. 
Thanks.

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
|A|M|A|D|O|DepartmentoDeInformaticaFCT/UNL 2825-114 Caparica 351+212958536
|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Preben Randhol]

On Tue, 9 Jan 2001 10:47:16 +0000 (WET), Mario Amado Alves wrote:
>--...compatibility is defined as a license that does not "impose any
>further restrictions". Yes the GPL is compatible with itself in this sense,
 ^^^^^^^^^^^^^^^^^^^^
 
>--Hmmm... So a license slightly more restrictive than GPL may be
                        ^^^^^^^^^^^^^^^^^^^^^^^^^

>--You are probably right. What I meant is an _open_source_ license (e.g.
>Ad=AAlib's) slightly more restrictive than GPL may be compatible with GPL.=

Remember a open source licenses does not mean it is a free license.

Read: http://www.fsf.org/philosophy/license-list.html
and : http://www.fsf.org/philosophy/bsd.html

-- 
Preben Randhol ---------------- http://www.pvv.org/~randhol/ --
iMy favorite editor is Emacs!<ESC>bcwVim<ESC>
                                         -- vim best-editor.txt

Re: Ada and Database

[Florian Weimer]

Mario Amado Alves <maa@di.fct.unl.pt> writes:

> --You are probably right. What I meant is an _open_source_ license (e.g.
> Ad�lib's) slightly more restrictive than GPL may be compatible with GPL. 
> Thanks.

I think I have posted the link to the Debian Free Software Guidelines.
They are identical to the Open Source Definition, and the last time I
looked, your license was not compatible with these requirements...

Re: Ada and Database

[Robert Dewar]

In article
<Pine.LNX.4.10.10101091042100.27577-100000@lexis.di.fct.unl.pt>

> --You are probably right. What I meant is an _open_source_
> license (e.g. Ad=AAlib's) slightly more restrictive than GPL
> may be compatible with GPL.=

I don't know how to be clearer :-)

NO license that is MORE restrictive than the GPL can possibly
be compatible with the GPL. There are indeed a number of
open source licenses that are incomaptible with the GPL, and
indeed the resulting software is not considered to be Free
Software by the GNU Project.


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Re: Ada and Database

[Mario Amado Alves]

> NO license that is MORE restrictive than the GPL can possibly
> be compatible with the GPL. There are indeed a number of
> open source licenses that are incomaptible with the GPL, and
> indeed the resulting software is not considered to be Free
> Software by the GNU Project. (Dewar)

Ok. Thanks. Now I know a bit more about GPL. I was not aware of such a
clash between it and "open source".

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
|A|M|A|D|O|DepartmentoDeInformaticaFCT/UNL 2825-114 Caparica 351+212958536
|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Robert Dewar]

In article
<Pine.LNX.4.10.10101091042100.27577-100000@lexis.di.fct.unl.pt>

> --You are probably right. What I meant is an _open_source_
> license (e.g. Ad=AAlib's) slightly more restrictive than GPL
> may be compatible with GPL.=

I don't know how to be clearer :-)

NO license that is MORE restrictive than the GPL can possibly
be compatible with the GPL. There are indeed a number of
open source licenses that are incomaptible with the GPL, and
indeed the resulting software is not considered to be Free
Software by the GNU Project.


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Re: Ada and Database

[Florian Weimer]

Robert Dewar <robert_dewar@my-deja.com> writes:

> NO license that is MORE restrictive than the GPL can possibly
> be compatible with the GPL. There are indeed a number of
> open source licenses that are incomaptible with the GPL, and
> indeed the resulting software is not considered to be Free
> Software by the GNU Project.

There are free software licenses which are incompatible with the GPL
(even the in the FSF terminology).  The GNU folks are not as zealous
as many people think.  Of course, they recommend against using these
licenses for new software, but they do not condemn the use of software
available under such licenses.

A few prominent examples of GPL-incompatible free software licenses
is are the original BSD license (with advertising clause), the Apache
License, the LaTeX license, the MPL, the QPL, and many more.

See http://www.gnu.org/philosophy/license-list.html for are more
complete list.

Re: Ada and Database

[Mario Amado Alves]

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On Sat, 6 Jan 2001, Robert Dewar wrote:

> In article
> <Pine.LNX.4.10.10101051416490.27577-100000@lexis.di.fct.unl.pt>
> 
> > Some of us can only understand _short_ legal texts,
> > because we become very sleepy after the first ten lines ;-)
> 
> I cannot tell you how many court cases wallow in chaos caused
> by non-lawyers thinking things like this, and writing down
> what they think are simple straight-forward agreements that
> turn out to be anything but.

They should be straight-forward, in fact like the hundreds of contracts you
do each day in plain natural language (not legalese), without any problem
of interpretation. Court law should proceed this way: first decided what
was rigth; then he would lookup for the laws to backup his decision.

> > I keep looking for an understandable ten-line digest of GPL
> > and "open source".
> 
> You will not find one, any ten line digest of a license
> agreement is going to be full of confusion, misleading
> implications, and errors.

Actually such digests exist, usually in licences as a note after the
reference to the GPL, saying "essentially what this means is ... [10 line
digest here]".

> I am sure there are people who would like to find a 4 page
> booklet clearly describing all of Ada.

4-page is perhaps too little, but it is a fact that nice Ada programs are
written without their author having gone through the whole ARM.

> If you don't clearly understand the GPL, how can you possibly
> make the judgment that your license (which I have not read)
> is compatible with the GPL?

I understand it roughly, from the digests. Perhaps sometime I will be able
to study it fully. It is simply a matter of personal priorities, really: I
still have the ARM to go through ;-) Fortunately I am a non-lawer.

  *
*   *

Also, the problems you mention sound characteristic of USA law. There is a
world outside USA, you know, with a lot of different law systems. The
Internet and open source must of course consider this.

  *
*   *

Thanks. I am learning a lot from this rare thread on Adªlib.

| |,| | | |RuaFranciscoTaborda24RcD 2815-249CharnecaCaparica 351+939354005
|M|A|R|I|O|
|A|M|A|D|O|DepartmentoDeInformaticaFCT/UNL 2825-114 Caparica 351+212958536
|A|L|V|E|S|                                                  fax 212948541
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Re: Ada and Database

[Robert Dewar]

In article
<Pine.LNX.4.10.10101081246290.27577-100000@lexis.di.fct.unl.pt>
> Also, the problems you mention sound characteristic of USA
> law. There is a world outside USA, you know, with a lot of
> different law systems.

Yes, but what I said about the need for legal precision and
knowledge applies equally well to these different systems.
For example, copyright law is much MORE complex in the EU,
because of the concept of moral rights.


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ada and database

[matias]

hello,
i'm new to ada.
i want to connect to a database(SageST) with a certain ODBC. could
someone please send me a sample code of how to do it.
thanks,

mati.

Re: ada and database

[Dmitry A. Kazakov]

On 28 Nov 2004 05:28:27 -0800, matias wrote:

> i'm new to ada.

Are you new to ODBC?

> i want to connect to a database(SageST) with a certain ODBC. could
> someone please send me a sample code of how to do it.
> thanks,

http://gnade.sourceforge.net (GNADE project)

This has ODBC bindings (thin). Provided you know ODBC, GNADE's ODBC is very
straightforward to use.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Re: ada and database

[David Botton]

There are some odbc examples in the Ada Source Code Treasury on AdaPower.com

David Botton


On 2004-11-28 08:28:27 -0500, matydavid@hotmail.com (matias) said:

> hello,
> i'm new to ada.
> i want to connect to a database(SageST) with a certain ODBC. could
> someone please send me a sample code of how to do it.
> thanks,
> 
> mati.

Re: ada and database

[bubble]

copy it from
http://en.wikibooks.org/wiki/Programming:Ada:Libraries:Database:GWindowswith
Ada.Text_Io;
use Ada.Text_Io;
with Gnatcom.Initialize;
with Gwindows.Databases;
use Gwindows.Databases;
with Gnatcom.Types;
with Gnatcom.Variant;
with Ada.Strings;
with Ada.Strings.Fixed;
with Ada.Exceptions;
with System;
procedure test is
     Connection : Database_Type;
     Recordset : Recordset_Type;
     customer     : Gnatcom.Types.Variant;
begin
     Gnatcom.Initialize.Initialize_Com;
     --make connection
     Open (Connection,
        "DSN=Northwind","your ID","your password");
     --make Recordset(ResultSet)
     Open (Recordset,
        Connection,
        "SELECT * from Orders",
        Dynamic,
        Optimistic);
     --start to process your bussiness solution
     while not Eof (Recordset) loop
        customer:=Gwindows.Databases.Field_Value(Recordset,"customerId");
        process(customer);--your customer procedure
        Move_Next (Recordset);
     end loop;
     ---release database resource
     Gwindows.Databases.Close(Recordset);
end test;