On Nov 8, 2011, at 8:34 PM, Paul Hoadley wrote: > Hello, > > I was recently reviewing an EO model of mine and noticed a flattened > relationship with a Nullify delete rule. I recalled part of an exchange > between Davids Avendasora and LeBer earlier this year: > >>>> And what should those be for the flattened relationship? >>> >>> I'm guessing that they should be "nullify" or "do nothing" >> >> Yes, only one delete rule should affect a given relationship. In fact, I >> always >> shy away from (nay, avoid completely) flattened relationships that hide >> objects >> I am actually interested in. In general, 'one path to the object' is the >> rule I >> try to follow. > > > So the advice is that the intended delete rule(s) should operate on the real > relationship chain, not shortcut via the flattened relationship. That's > fine, but are Nullify and Do Nothing really interchangeable on a flattened > relationship, as it's almost suggested above? It's important because the > default is Nullify, so all flattened relationships have that rule unless you > change them. But depending on whether that rule is applied before or after > the rule(s) applied over the real relationship chain, Nullify might end up > giving you the wrong semantics. Shouldn't all flattened relationships have a > Do Nothing delete rule (at least by default)? > > > -- > Paul. > > http://logicsquad.net/
Not all... at least not flattened many to many. Those cascade. Which led me to a surprising find as well. The opposite side of that cascade is nullify, which I thought was incompatible with cascade. But, evidently, it works and I can see why it would be needed on the other side of the delete. Ramsey _______________________________________________ Do not post admin requests to the list. They will be ignored. Webobjects-dev mailing list (Webobjects-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
