On Saturday 29 Jun 2002 5:51 pm, Florent Guillaume wrote:
[Redirecting to zope-dev]
Carl Rendell <cer@sol43.com> wrote:
Has anyone on the list ever 'set' the modification or other date attributes on an object in the ZODB? I've looked at the bobobase_modification_time() call and found it looks at an attribute [_p_mtime] for an object, but have yet to discover what controls the setting of that attribute, or if that is the attribute to set?
I'm familiar with changing these on items in a file system, but performing the same task on an object in the ZODB has me stumped right now.
I looked a few weeks ago, and it's deep in the C code, and grep-proof besides :-) Look in ZODB/cPersistence.c, grep for "'m'" (with single quotes).
My conclusion was that it was very tied to the ZODB and that setting it would probably break the serial or transaction mechanisms.
That conclusion is correct. _p_mtime is the timestamp of the transaction from which that object was loaded. It is used at the end of a transaction if you modified an object, to verying that there has not been a newer revision of the object since the one that was modified. If you want to define your own modification time behaviour, the recommended approach is to define your own seperate attribute.