Re: [gnome-db] Re: Multiple queries in report stuff

[Vivien Malerba <malerba gnome-db org>]

On Wed, Jan 22, 2003 at 12:23:12PM +0100, Santi Camps Taltavull wrote:
> > -> add a simple function to create a Query representing "SELECT * FROM
> > my_table": a button in the list of tables tab. Creating such a function
> > is already available today but the user must click on the "new query"
> > button in the queries page. 
> > 
> > -> create a new GnomeCanvasItem to represent a Query object on a canvas:
> > a CanvasQuery object (modeled for example after the CanvasQueryView).
> > This GnomeCanvasItem will:
> > 	- show the fields in a query
> > 	- show the parameters of a query
> > 
> > -> create a ReportView object (inherited from a GnomeCanvas object,
> > similar to the CondsView) to display CanvasQuery items and enable
> > connection between them as shown in the proposal I sent yesterday.
> > 
> 	I think I would be very nice that, when you add a table that is relationed (via a foreign key) with another already in the diagram, connections be created automatically.

This can be done quite easily (just a parsing of list of joins and
associated conditions).

> 
> > ..-> extend the DTD to store reports definition (queries and their
> > relations, text, etc) and write the actual code which does the job of
> > generating a report description which can be sent to libgda for
> > "interpretation".
> > 
> 	Referencing the DTD in libgda/report should be enought, I think.  Also, to generate the report description, libgda-report will provide all the functions needed, so report is always interpreted and validated.

It's more than that: in the mergeant file, we need to store all the
informations which are used to generate the XML file for the report, not
the report itself. If we only had the report itself (the report XML
file), then we would not be able to present the user exactly the same
GUI he had when he first created the report, and it would be more
difficult to re-genetare the report if for example the queries changed.


> 
> > I know this is quite a lot of work, but then we have something quite
> > generic which uses the power of the Query object.
> > 
> > Tell me what you think about this.
> > 
> 	It sounds very nice.  But I don't see how other elements of the report will be designed, like labels, lines, pictures, pageheaders or pagefooters, for instance.   It will be another canvas where these elements are designed graphically, or how are you thinking to do this ?

I feel quite confident we can make a nice GUI using a canvas and some
widgets on it. Have a look at the DIA file I posted earlier, it is a
basic preview of the canvas (without the report header, page header, etc
we could add later). Tell me if you have some problems reading that DIA
file (there are sometimes problems with fonts...)

Cheers,

Vivien