Re: [gnome-db] [mergeant] Status ?

["Vivien" <malerba gnome-db org>]

> Vivien wrote:
>
>>>Next number will be 1.0.0 :-)
>>
>> There is still quite a lot of work before 1.0.0!
>>
>
> Is there a roadmap ?
> I found
> http://mail.gnome.org/archives/gnome-db-list/2003-June/msg00067.html
> but can't understand purpose of libmergeant vs. libgnomedb

Libgnomedb provides widgets on top of libgda; libmergeant uses libgnomedb
and also provides widgets (form, grid, etc) but they are more powerfull,
and the big drawback is that they require a data dictionnary and they
consume more memory. Depending on what an application has to do, it may be
wiser to use libgnomedb's widgets or libmergeant's widgets.

For instance the libgnomedb's form widget works with a GdaDataModel and
lets the programmer display data contained within the data model. AFAIK,
it does not allow direct editing of the displayed data, and does not make
the modification queries when data is modified by the user. Libmergeant's
widget works on a SELECT query objet and does all the work by itself
(decide which columns will be displayed, which will be editable, which
will have a combo box, creates the UPDATE, DELETE and INSERT queries,
etc).

For example the SELECT query:
SELECT t1.name, t1.phone, t2.role FROM employee t1 INNER JOIN roles t2
WHERE t1.age>35
will create a form with a text entry for t1.name, one for t1.phone, and a
combo box with all the t2.role values, and display the result of that
query in it.

At one point in the future, it is possible that these two libraries merge,
but for now they are separate.

For now, the Gnome-Db 'package' has the following:
-> a low level, no GUI toolkit (libgda)
-> a GUI toolkit on top of libgda (libgnomedb)

and hopefully will soon have:
-> a high level GUI toolkit on top of libgnomedb and libgda (libmergeant)
-> a general-use application (mergeant) which uses the other libraries

>
>>
>> When first used on a data-source, libmergeant creates its dictionnary
>> from
>> the DBMS, and then can store it to an XML file (which can be used in
>> subsequent connections to that data-source).
>>
>
> file with name of tables, attributes, etc. ?

Yes, a very complete description of the database.

> where are this files ? (~/.gconf/apps/libgda/Datasources/) ?
> if so, file ~/.libgda/config shouldn't be in .gconf dir ?

This is hidden from the user, but it will probably be .libmergeant (or
.libgda/mergeant) or something like that.


>>>>
>>>
>>>How can i start to change it ?
>>
>>
>> -> Do a checkout of the libmergeant module _only_ to build the doc
>> (which
>> is not yet present in the mergeant module).
>
> which branch ?
> in HEAD intresting is only 'mgconf.html'

HEAD branch, then build the module (and don't install it), the doc will be
in doc/C/html

>
>> -> Do a checkout of the mergeant module and start working in the
>> frontend/
>> dir (not src/ since it is for the old version).
>
> v.0.50.0 ?

Yes, in frontend/ is 0.50.0 version (the one to work on) and in src/ is
0.12.0 version (to be trashed).

>>
>> Mergeant should also be run with either the name of a data source or the
>> name of a XML dictionnary to load.
>>
> should == can ?

Yes.

Cheers,

Vivien