[Zope] non-undoable storage

[Milos Prudek]

I have a couple hundred Articles (class instances) in my ZODB. Most 
instances are 200 kB, some are much larger. One of the Article 
properties is Number of times the article was read. Any increment causes 
ZODB to grow by the size of the given instance, due to the fact that 
ZODB will append a new version of the whole 200 kB or 2MB instance just 
because a single byte was changed.

Consequently ZODB grows several hundred MB in a single day even if no 
new article is added.

This calls for some form of non-undoable storage.

One possibility is to move the "NumberOfReaders" attribute from ZODB to 
my SQL server. Not a problem, but I'm not sure what is the best way to 
maintain connection between ZODB instance (it can appear at different 
places in ZODB directory structure and it can be moved from place to 
place with Cut and Paste in ZMI) and SQL table. Connection means SQL key 
column. Instance ids cannot be used as a SQL key, because they are 
nonunique - each folder has a sequence of instances numbered 1...x. So 
there are over ten instances named "1". Instance addresses = URLs could 
be used but I would have to write my own methods / interfaces for moving 
Articles in the directory structure to maintain the connection between 
ZODB and SQL table.

Is there an obvious elegant solution that I am missing?


-- 
Milos Prudek