[Zope] trees, SQL and ODB's

Hannu Krosing hannu@tm.ee
Sun, 09 Sep 2001 23:37:08 +0500


tom smith wrote:
> 
> > I have a little rule of thumb that if your data is tabular, stick it in a
> > RDB, if it's tree-like, stick it in an ODB.
> 
> I have a little rule of thumb, if assistance starts with "I wouldn't start
> from here if I was you", stick it where the sun don't shine!
> 
> :-)
> 
> Tom
> 
> p.s I'm not storing my data in a relational database out of wilfulness.
> p.p.s What is your data is part tabular and part tree-like (like most data),
> where does that leave your thumb?
> p.p.s Maybe I'd better rephrase my question, here goes...
> 
> How do I make an iteractive DTML that calls itself AND passes all the
> namespaces (to things such as ZSQL methods)?

If you read ZSQL documentation you see that it gets it's args from a few 
places only so the best advice is to explicitly pass the args you need
in 
your ZSQL-DTML. This is done for security. If you really need to pass
some 
namespace, pass that namespace explicitly and use it from your DTML 
explicitly.

About that tree question (if I remember it correctly) the argument
really 
_has_ to be called parent id everywhere in the tree tag where the
original 
example uses parent_id, so name your ZSQL method's argument parent_id :)

btw, I have stopped using that method and have instead written a small
class 
in an External Method that has all the required methods/properties a
dtml-tree 
tag needs.  It's not suitable for very deep trees as it read's all of
the tree 
when used, but it can cache it's data so it is not as bad as it sounds
in 
a general case.

So even I did start from there when I was you, but I don't do it anymore
;)

------------------
Hannu