Dimensions?

[Christopher Browne]

On Wed, 27 Sep 2000 10:46:27 +1000, the world broke into rejoicing as
"Phillip Shelton" <shelton@usq.edu.au>  said:
> True. I think what I want is to be able to report on the transaction from
> both clothes and shoes.
> 
> Others have shown that if I use a well defined tree I can roll-up my account
> info  and have it do what I want it to.

... And in perhaps-overly-brief response to the multiply-expressed
question,
  "What if it's not a tree?"

... I'll just respond that if it's a tree, then rolling things up to the
right point is a completely linear matter, and allows you to maintain
the property that it all adds up nicely.

If, instead, it's not a tree, but a general graph, where "Shoes"
could occur anywhere, rather than adding things up, reports would
need to use more general set-theoretic operations like intersections,
unions, and such, where there is considerably more risk of accidentally
double-counting transactions and otherwise "messing up," and, arguably
more importantly, making it harder to understand/predict exactly what
is happening because there's _NOT_ the "linear" relationship that "all
the transactions are in this subtree."

The engine code required to support "connected graphs" isn't the nasty
part; it's probably tough to get right, but certainly not impossible.
The _NASTY_ part would be to put together a user interface that you can
implement and that users will understand.
--
cbbrowne@acm.org - <http://www.ntlug.org/~cbbrowne/lsf.html>
Microsoft spel chekar vor sail, worgs grate !!
-- <leitner@inf.fu-berlin.de>, Felix von Leitner