[Zope-DB] working with zope rdbms transaction mgmt

[M.-A. Lemburg]

Jim Abramson wrote:
> Hello all,
> 
> As has been mentioned many times on that list, calling explicit 'commit' on the db connection you
> are using during a Zope request is a no-no...
> 
> My question is, if i grab a reference to the cursor from some db connection inside a python
> script, and do a bunch of statements directly on this cursor, and something goes wrong on the nth
> statement (i.e. uncaught Exception), should I expect all of the statements performed using that
> cursor up to that point will be automatically rolled back?

Yes.

> If yes, next question is, if I trap an exception that's raised during the nth statement, and
> proceed (using the same cursor) to the (n+1)th statement, and the REQUEST wraps up cleanly,
> should I expect all of the successful statements will be automatically committed?

Yes.


That ways easy :-)

Database transactions are handled on the connection, not the cursors,
so unless you connection dies in the middle of processing a request,
anything you do on the connection will get committed if Zope finds
that processing was successful, that is in particular, no unhandled
exception was raised.

-- 
Marc-Andre Lemburg
eGenix.com

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