Seaborne, Andy wrote:
>
> Looking at the tests, there seems to be no transaction control for the
> Jena tests. With JDBC, each operation will get an implicit transaction
> wrapper. This is bad for read access and very bad for update.
>
> public void startTransaction(/*=RepositoryType=*/Object/**/ repo) {}
>
> I don't have experience of using Derby or its JDBC driver but it does
> appear to support transactions so maybe it isn't a no-op. As triples
> are small, the transaction overhead can be more than the operation
> itself.
I remember running the transactions but not getting any differences. But
thanks for pointing it out.
I will run the tests again in about 2-3 weeks and post any updates.
Also, just to make more apples-to-apples comparison, I will also adding
both Jena-MySQL and Sesame-MySQL to the results.
If there are any other suggestions/contributions please let me know in
the next week or so, and I will be able to push things out in one go.
Also, thanks to Ian Davis for pointing out a bug...
> ...
>
> public void commitTransaction(/*=RepositoryType=*/Object/**/
> repo) {
> model.close();
> model = null;
> try { conn.close(); } catch (SQLException e) {}
> conn = null;
> getModel();
> }
>
> opening and closing models will achieve transaction effects but it's
> expensive. You shouldn't need to open and close connections - if there
> is some reason why this needs to be forced for Derby, I'd be interested
> in hearing about it. ...
This is unfortunately a limitation in the Jena-Derby driver. See
'issues' at
http://people.csail.mit.edu/vineet/jena-derby.html
Vineet
Received on Fri Jan 13 2006 - 07:23:31 EST