Re: [Tracker] How to get newly added audio files?

[Philip Van Hoof <philip codeminded be>]

On Wed, 2011-03-30 at 18:02 +0900, simon hong wrote:
> 2011/3/28 Adrien Bustany <abustany gnome org>

> > I guess you can use the tracker:modified or tracker:added properties here
> > (I'd recommend tracker:modified, but am not sure how it's defined for newly
> > saved resources).
>
> Now, I use "SELECT nie:url(?u) WHERE {?u a nfo:Audio}" to get audio files.
> I don't know how to use above properties (tracker:modified or
> tracker:added)  for fetching newly added files.
> Can you give some advice how to make sparql query for my purpose?
> Or any documentation or guide for sparql will be appreciate.

So for synchronization what you do is the following:

SELECT MAX (tracker:modified (?r)) { ?r a rdfs:Resource }

And you store the result

Then next time you start your application, to get the newly added and
the changed resources you put that stored value in $stored and you do:

SELECT ?r { ?r a nfo:Audio .
    FILTER (tracker:modified (?r) > $stored) }

Note that this is for nfo:Audio, but it works with any rdfs:Resource

> > Note that instead of looping, you could also use the GraphUpdated signal to
> > get updates in real time.
>
> GraphUpdated signal is what I wanted ^^; It works well :)

If GraphUpdated works for you, then indeed use that.

Cheers,

Philip


-- 


Philip Van Hoof
freelance software developer
Codeminded BVBA - http://codeminded.be