[Zope-DB] Controlling Z SQL caching

[Ian Bicking]

I've decided that I definitely need some caching in a database-driven 
application I'm working on, but I need to be able to invalidate the 
cache on a query.  I don't see any way to do that with Z SQL methods. 
It would be ideal if I could just pass an extra keyword argument in 
(like nocache__=1), and it would get rid of any caches on that query. 
This looks like a really easy change to make in DA._cached_result (and 
__call__, to pass the argument through).  But it doesn't seem like I 
should have to patch Zope for something so basic.  Is there another 
technique that I'm missing?

Actually, I'm not really sure if turning off caching for a specific 
query will work... maybe purging the entire cache for a query would be 
better.  But there doesn't seem to be an interface for that either.

Thanks for any ideas...
   Ian