This has already been implemented in CVS as a psql \set variable:
ON_ERROR_ROLLBACK = 'interactive'
and will appear in 8.1.
---------------------------------------------------------------------------
Michael Paesold wrote:
> Tom Lane wrote:
>
> > "Michael Paesold" <mpaesold@gmx.at> writes:
> > > On the other hand, the scenario of a psql option (read: I have
> > > given up the idea of a backend implementation) to rollback only
> > > last statement on error is quite different.
> >
> > Sure (and we already have one for autocommit). But I thought you were
> > asking about a backend implementation.
>
> I have implemented what I have suggested for psql. I have attached a first
> patch for review here, because I have a few questions. Also I want to make
> sure the whole thing is reasonable.
>
> I have named the option "IMPLICIT_SAVEPOINTS", because that's what it is. If
> someone has a better name that would describe the purpose of the feature, I
> am happy to change it.
>
> The feature is activated, if
> * \set IMPLICIT_SAVEPOINTS 'on'
> * connection is in "idle in transaction" state
> * psql session is interactive
>
> The code executes an implicit "SAVEPOINT pg_internal_psql" in
> common.c/SendQuery to which it will try to rollback to, if the executed
> query fails.
>
> Open questions:
> * Should psql print a notice in the case of that rollback?
> Something like "Rollback of last statement successful."?
>
> * What is currently missing, is a detection of \i ... obviously this feature
> should not be used for each query in \i. Perhaps only for the whole \i
> command?
> So what should I do to detect \i?
> Add an extra argument to MainLoop, SendQuery and process_file()? (many
> changes)
> Add a global variable in common.c/h (e.g. bool
> deactivate_implicit_savepoints) that can be used in process_file to
> temporarily deactivate the code path?
> (more local changes, but rather a hack imho)
>
> Please have a look at the patch and comment.
>
> Best Regards,
> Michael Paesold
[ Attachment, skipping... ]
>
> ---------------------------(end of broadcast)---------------------------
> TIP 9: the planner will ignore your desire to choose an index scan if your
> joining column's datatypes do not match
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073