> I don't understand the problem here. Forum.query.count() should return
> the number of contexts of "Forum" type.

The Forum-number is not of interest here.

The member_count is about the number of participants in the given context. For 
a project, these are the project members. For a forum, these is the count of 
the set of users that have one of the groups the Forum is intendet.

And I need to sort the context based on that information. For efficiency (this 
will be needed very often) I want to do this in the database - not on the 
resulting contexts. So I store the count in an extra column.

And this column of course needs to be updated whenever the underlying data 
used to compute it changed. I admit though that there are many special cases 
that are hard to track (to say the least), but nevertheless the question 
arose if I could somehow automate some of the work using events.

> > So I planned to introduce a "compute_member_count"-method on each
> > subclass of context that will be invoked whenever anything in the
> > relations of the Contexts changes.
> >
> > For that, I'd need some sort of hook that is invoked for each modified
> > object so that I can invoke my compute_member_count-method.
>
> Don't the elixir events (probably before_insert and before_delete) fit
> the bill here?
> http://elixir.ematia.de/trac/browser/elixir/trunk/tests/test_events.py

I didn't know of them, I will have a look - thank you.

Diez

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"SQLElixir" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at 
http://groups.google.com/group/sqlelixir?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to