libgda vs. gnucash [was Re: GnuCash page on GO site]

[Linas Vepstas]

On Wed, Mar 03, 2004 at 05:35:32PM +0100, Rodrigo Moya was heard to remark:
> On Wed, 2004-03-03 at 10:24 -0600, Linas Vepstas wrote:
> 
> > 
> > -- an object query system. libgda does not.
> > -- a uuid system. libgda does not.
> > -- an object persistance infrastructure. libgda does not. 
> > -- a multi-user object caching and cache-coherence system. libgda does not.
> > -- a data-set partitioning system. libgda does not.
> 
> We are making progress though. since now we know what you need from
> libgda. 

Are you sure you want to implement these features? It wasn't clear
to me if these were within or outside of your project scope.

> So, next question is, how separated from gnucash are each of
> those features? 

Well, I' describing the core gnucash object system.  *if* there
was another system that really did support all of these features, it
would not be hard to replace the whole core.  But it would be
impossible to replace a part of the core.  Each of the features
is required for the other parts to work correctly.

> Would it make sense/be not a too hard work to try to
> integrate them into libgda? 

I don't know.  It might be hard, there are a variety of subtle 
issues, some of which we haven't solved ourselves yet.  

One that has been dogging me is the correct way to split up 
a dataset across multiple files.  GnuCash startup time takes
a long time if you have a large data fileset.  So I would like
to split it up, while still allowing queries over older data 
in older files if the user needed that. 

One problem is that each dataset must have a copy of all of
the accounts.  When working with mutiple datasets, there is 
the problem of having what looks like multiple, identical
copies of the account.  So, we have to be able to identify
these copies as being "the same account".  On the other hand,
the newer datasets may have changed/modified the account, so 
these "identical" records are not really the same.  There's
a subtle interplay between the UUID's used to identify accounts,
the possible existance of backups made by the user, and the
copy-on-write semantics so that we can correctly manage 
changed/modified versions the objects.

Derek has been arguing that we supprt SQL only, so that we can
completely avoid/ignore this issue.  I think I've discovered 
a simple/easy answer, but haven't implemented it yet.

> or to change them to use libgda for the
> basic data access and management?

Can libgda write out XML files? If so, does it need the DTD to do this,
or does it use schema's?  

--linas

pub  1024D/01045933 2001-02-01 Linas Vepstas (Labas!) <linas at linas.org>
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