RDFLib/rdflib-sqlalchemy — pull request #8 by fconil (2014-02-10 16:28:24+00:00)
Title: cmdTripleDict was not filled in the beginning of addN

When testing rdflib-sqlalchemy to write to differents stores, we used something simplar but similar to sp2b.py and we noticed that the item where not written in the store.
It seems to be a problem in SQLAlchmy.addN() method.

```python
gm = rdflib.Graph()
gm.add((rdflib.BNode(), RDF.type, FOAF.Person))
with BZ2File(".../rdflib-benchmark/sp2b/500.n3.bz2") as f:
gm.parse(f, format='n3')
g = rdflib.Graph(store="SQLAlchemy")
g.open("sqlite:///test-triples.db", create=True)
g += gm
g.commit()
print "Graph length in memory : %d" % len(gm)
print "Graph length in SQLite : %d" % len(g)
```