On Tue, 2016-01-19 at 14:44 +0000, Ian Jackson wrote:
> Ian Campbell writes ("Re: [PATCH OSSTEST v2] cs-adjust-flight: Add jobs-
> rename command which applies a perlop to job names"):
> > On Tue, 2016-01-19 at 14:25 +0000, Ian Jackson wrote:
> > > And if that happens, there might be entries in the steps table which
> > > ought also to be renamed. If you don't rename them you will trip the
> > > foreign key constraint.
> >
> > But fail immediately in this invocation of cs-adjust-flight with a
> > (hopefully) comprehensible SQL error spew?
>
> Yes.
>
> > Or is that the distinction between INNTIALLY IMMEDIATE vs DEFERRED you
> > were
> > trying to get at?
>
> Indeed. With the current (and likely future) configuration of the
> constraint, the UPDATE statement will fail and the transaction will
> not commit. So none of the updates in the invocation will take
> effect.
>
> > Having stuffed the flight in this way would it have effects elsewhere
> > (i.e.
> > on production flights) or do you just get to keep both pieces of this
> > particular flight?
>
> If the constraints were changed, you might manage to use
> cs-adjust-flight to produce strangeness in the flight you were
> adjusting. If that flight were later exposed to archaeologists it
> might contain lies. TBH this seems far-fetched.
Indeed, especially since:
* Archaeologists typically don't look at play flights (or if you ask them
to you should expect breakage).
* If a real flight somehow got into this state (via running:N or being
constructing) then I would expect it would trip over the constraint
before it could complete, and therefore never get to its intended
blessing in the db, and would again be ignored by archaeologists in
general I think?
* cs-adjust-flight already stops one from messing with a completed flight.
Ian.
Ian.
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