Re: Dynamic data model, locks and performance

On Wed, Jul 28, 2010 at 10:15 PM, Pierre Thibault
<pierre.thibault1@gmail.com> wrote:
>

> What I would like to do is enable users to create their own data model. Enable them to create a model and make > it evolve. For example, it would be cool to create a model to represent car adds. Then, the buyers can search adds > using the previous model with specific criteria like the color of the car they want.
>

Sounds like a standard parts explosion or component / subcomponent
hierarchy?  The most general form has two pieces:

1) a tree model of some form. I like the set / subset model that Joe
Celko popularized (search the archives for other references to it from
me);

2) an extensible set of containers to hang of the tree.  Here I like
to use a strongly typed version of the Entity Attribute Value (EAV)
type model;

Those two pieces on their own are so general that you can't really
scale the results very far.  However, if you've got some specific
goals in mind I might be able to provide some hints.  If you're an
IEEE member I can point you at a presentation I did on the basics (I
think)...

--
Peter Hunsberger