[Zope-CMF] Re: [Zope-dev] _p_deactivate() and _v_ variables?

[Dieter Maurer]

Toby Dickenson wrote at 2003-10-10 07:54 +0100:
 > ...
 > A while ago there was a discussion on zodb-dev about _v_-like attributes that 
 > would be automatically cleared at the end of a transaction. Do we need 
 > something similar that guarantees it will _not_ be cleared until the end of 
 > the transaction?

This definitely is necessary for the "_v_" attributes that hold
connections to a relational database.

If such a "_v_" attribute is flushed, the next access to the DA
(in the same request) reopens the database. As this is a new
connection, it does not see the changes made by the previous
connection (in the same request).

This can lead to very nasty non-deterministic and almost ununderstandable
errors.


Dieter