[ZODB-Dev] Re: Local transactions and mount points

[Dieter Maurer]

Matt Feifarek wrote at 2004-2-23 13:18 -0500:
>Can you explain this a little further?
>
>We'd like to try setLocalTransaction(), but want to understand your point.
> ...
>Dieter Maurer wrote:
>>Christian Robottom Reis wrote at 2004-2-19 20:14 -0300:
>> ...
>>>I like
>>>setLocalTransaction() for that reason -- it makes things so much
>>>simpler to grasp.
>>>    
>>>
>>
>>But (I fear) it does not work when you have mounted in storages.


A transaction can (in principle) work as a commit monitor
for a set of commit clients. Such clients are connection
to several ZODB storages, relational database connections,
transactional mail services, ....
The transaction coordinates the various connections in a two phase
commit during commit.

For this to work, all connections must have the *same* transaction.
This is not the case in the "setLocalTransaction" mode.
You can use this mode only when you have a single (ZODB) connection:
no support for multiple ZODB connections, no support for connections
to relational databases or other transactional subsystems.

-- 
Dieter