Re: recursive deletion (Re: Model questions)

On 29 Jan 2013, at 13:23, Ashok Malhotra wrote:

> Hi Roger:
> Would you agree that recursive deletion is important in some cases?

I do! In lots of cases in fact.

I also agree with the sentiment in this blog post from Michael
http://webofdata.wordpress.com/2011/05/29/ye-shall-not-delete-data/

> I don't think we want to make it the default but I think it is useful
> to allow it, perhaps with higher cost and complexity, to cover the
> situations where it is required.

maybe it is a MAY (?)

Roger

> All the best, Ashok
> 
> On 1/29/2013 3:28 AM, Roger Menday wrote:
>>> 
>>> 2. When a collection is deleted are its members deleted also?
>>> This is the composition vs. aggregation question.  We closed issue
>>> http://www.w3.org/2012/ldp/track/issues/25 but I don't think
>>> the matter is settled.
>>> 
>>> We agree that both composition and aggregation are needed but we
>>> don't have agreement on mechanisms.  http://www.w3.org/2012/ldp/track/issues/34
>>> covers a part of it.
>>> 
>>> There seem to be three proposals:
>>> A.  Use an attribute on the collection to indicate composition or aggregation
>>> B.  Use two separate classes for composition and aggregation
>>> C.  Delete all members when a collection is deleted.  Use links to cover the
>>> aggregation case.
>>> 
>>> Perhaps we need an issue to decide on the mechanism.
>>> 
>>> This is my assessment of the situation.  I know I don't have to say this to this
>>> group, but don't be shy and send mail if you disagree
>> Hi Ashok,
>> 
>> Thanks for your summary. You asked for opinions :) and so, I will offer you my opinion on your second question. My opinion is that recursive deletion of resources is a bad idea and we should drop it !!
>> 
>> I don't see that once a resource goes out into the big wide world why it should be cut short when their creator is deleted.
>> 
>> For recursive delete to work, this requires that a child resource to be kept strictly under the management of the parent. I don't think that this is way things should work, and it is definitely not the way that the web works either. It might work sometimes, but, it certainly won't be able to work all of the time. The creation semantic of LDP needs to be more flexible than that. It needs to be able to accommodate resource creation on different servers, moving resources, persistent resources, etc etc ...
>> 
>> Roger
>> 
>