- From: Tim Berners-Lee <timbl@w3.org>
- Date: Wed, 14 Nov 2012 12:38:02 -0500
- To: Melvin Carvalho <melvincarvalho@gmail.com>
- Cc: Semantic Web <semantic-web@w3.org>
Received on Wednesday, 14 November 2012 17:38:12 UTC
Responding to the original message, we saw this as a need in general to be able to
do something indivisible, for generating cloakroom tickets or next ids or
whatever. In general, distributed systems must have some form of P/V flag.
So the plan is currently:
DELETE { :c1 :value } INSERT DATA { c1 :value 23}
must then give an error if the value has already been incremented by
someone else. Then the client rolls back, re-reads the RDF resource,
and tries again in a moment.
See "Note 409 conflict" section of http://www.w3.org/DesignIssues/ReadWriteLinkedData.html
Tim
On 2012-11 -10, at 06:54, Melvin Carvalho wrote:
> Is there a pattern for incrementing a literal counter?
>
> Alice stores turtle in http://example.org/counter
>
> The initial operation should generate something like
>
> <#> <#counter> 1.
>
> Then the subsequent operation
>
> <#> <#counter> 2.
>
> And after that.
>
> <#> <#counter> 3.
>
> And so on ...
>
> Is there a neat way to do this in distributed way? SPARQL update? Maybe using Etags?
Received on Wednesday, 14 November 2012 17:38:12 UTC