[gnome-db]Re: XML Queries

[Malerba_Vivien stna dgac fr]

Le jeu, 15 fév 2001, vous avez écrit :
> On Tue, 13 Feb 2001 Malerba_Vivien stna dgac fr wrote:
> 
> > * Gerhard has produced a first working version of the XML query
> > implementation which contains a new DTD (not finished yet), and a C
> > library to convert XML queries to SQL. He is also now working on using
> > XSLT rather than pure C to do the job.
> 
> I'm having a look at the DTD but it's difficult to understand every
> element. We should add a little documentaion in it. Example help but are
> not enough :( I'll add comments and examples as I go through it.
>

I plan to document it but for now the easiest thing you could do is ask Gerhard
about the DTD details since he wrote most if not all of it.
  
> > * Pau has an awk parser to have the reverse path (from SQL to create
> > XML) that is based on the old xml-query.dtd in CVS
> 
> It works now with the latest DTD, only the create part, but it's very
> precarious, without error checking. It works in simple cases as mysql
> dumps :) Not bad to start working without having to retype the whole DDL
> again. It also underdtands the foreign keys. I'll extend it in the coming
> weeks but meanwhile if somebody needs it, just drop me an email.

This is a nice and usefull piece of software, but I wondered if it would not be
easier to use a parser (lex/yacc) to do the job (and maybe start from the
MySql or Postgres ones) rather than awk; I believe that as you introduce more
functionnalities, it will grow to a point where it is difficult to maintain
(from my own experiences with awk anyway).

What do you think?

> 
> Pau

Cheers,

Vivien