Re: Order of before_delete trigger in docs

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( sorry for the delay, 'been sleeping %-| )

On Jun 27, at 08:47 (+0100), 'Tony Bowden' wrote:
> On Mon, Jun 27, 2005 at 10:44:32AM +0300, Marius Feraru wrote:
>> Remember Tony that Bill is using Class::DBI::Loader magic ;-)
> I don't use CDBI::Loader so I dont' know what it does.

Neither do I, just made an (somehow) educated guess ;-)

>> CDBI::Loader seems to be automagically creating all possible
>> relationships between his tables, getting to where I stated in my
>> previous message.
>
> I don't understand this.

I don't understand what you don't understand, so, for our brains' sake, 
I just baked a "good morning" test script to demonstrate this flaw.
Attached.

I made a simple example using two classes: "Actors" and "Roles". Let's
say each Actor may have multiple (has_many) Roles and a Role is
occupied by a single (has_a) Actor. Now, presuming that each Role must
be occupied, we have to disable removing Actors that have some
Roles attributed to themselves. Hence, using a before_delete trigger on
Actors should do the trick, but... run the test script :)

a) ./cdbi-test.pl
  ^ should work as expected
b) ./cdbi-test.pl 1
  ^ fails, as triggers chain (not so bad) in reverse order (definitely
    bad).

hopefully now it's all clear.
- -- 
Marius Feraru                                   http://www.altblue.com/
"It isn't easy being the parent of a three-years-old.
  However, it's a pretty small price to pay for having somebody
  around the house who understands computers."
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