[Tracker] SPARQL: Drop Graph deprecated

["Mildred Ki'Lya" <mildred593+ml tracker gmail com>]

Hi again,

I created an indexer for tracker 0.8 and now with tracker 0.10, it
doesn't work anymore: Use of DROP GRAPH is deprecated

I was never clear on what exactly were the sparql requests to add new
objects to the database:

At first, I just used the simple form:
  INSERT { <file:///.../mbox#1> a nmo:Email . <file:///.../mbox#2> a
nmo:Email . ... }
But i had a problem: when a new email was added to the mbox file, I
re-parsed the complete file and issued the commands to insert the
first mails that already existed. Consequently, tracker told me that I
tried to add properties that already existed.

Then, I think I understood how it worked, and used the INSERT INTO
command combined with DROP GRAPH:
  DROP GRAPH <file:///.../mbox#1>
  INSERT INTO <file:///.../mbox#1> { <file:///.../mbox#1> a nmo:Email . }
  DROP GRAPH <file:///.../mbox#2>
  INSERT INTO <file:///.../mbox#2> { <file:///.../mbox#2> a nmo:Email . }

But now, DROP GRAPH is deprecated and apparently, this makes my
tracker-extract fails on all mbox files.

What is the correct way of doing things.

if possible, I'd rather override existing objects and not test if they
are already in the database for three reasons:
- It simplifies my code
- I still have to parse the e-mail
- I the second time, I might generate additional information (like
tags associated on the fly)

How should I do things?

Thanks,

Mildred