[thesite] Re: multiple categories (was CodeFest: Flights and LOTTD)

[rudy]

> Rudeman already has the db structure laid out for this,
> though i don't believe it's implemented in any of the
> databases.
>
> http://members.evolt.org/rudy/oracle4.gif


multiple categories per article?  yes the structure is there

and if i had been even marginally more productive lately, we should already
have had one working example in f.e.o by now (matt, see comment below)

please note that multiple categories is *not* the same animal as multiple
centers (to use the old word for the classification of our articles --
Backend, IA/Usability, Commentary, etc.)

if i recall from 1999 (i think it was), the discussion on multiple centers,
which was long and lively, concluded that we did not want an article in
multiple centers, nor did we really need it -- the rationale for this, if i
recall, was that people are unlikely to miss an important article by
looking exclusively in one center, they would probably use the search
function, in which case relevant articles would show up no matter what
center they're in

second major point is that there definitely are more categories than just
the centers -- but none are as yet implemented, simply because of the
backwards compatibility problem with existing code

this backwards compatibility problem is not one that i have personally
verified -- perhaps jeff can chime in here -- but it is one that i
anticipate

the problem arises in any query that utilizes the categorys table on the
assumption that all the rows in it are centers (which was the initial
evolt 1.0 implementation)

for example, the dropdown list on each w.e.o page is generated from the
categorys table, but what we must do is ensure that the query selects only
those rows where the cattype foreign key points to the cattype row for
"Center" (this could be hardcoded as an absolute value of the FK, no need
to do the actual join to the cattype table)

okay, given this background, you can now see that the introduction of the
second cattype after "Center" has a potential backwards compatibility
problem

i hope this explanation is helpful

perhaps this could be looked at in the next couple of weeks to see what, if
any, changes to the code would be necessary to eliminate the problem of
introducing additional categories


rudy


matt, this backwards compatibility problem is not the reason i have
procrastinated the implementation of your f.e.o attributes

there's just a lot going on here in my life right now, and working on
anything for more than a couple of hours at a time is proving to be quite
difficult

but i haven't forgotten, and it's right up there on my list of things to do
(in fact it's number three, behind the salons database and some changes for
a paying client -- not that i have a lot of these, but i do have to keep
them happy...)