On 28/08/13 08:24, Davide Rossi wrote:
Davide,
First of all, thanks for your answers.
When I start Fuseki, I bind it to a still existing (empty) dataset. First I
create dataset:
File f = new File("myDataset");
if (!f.exists()) {
f.mkdirs();
Dataset tdbDataset = TDBFactory.createDataset(f.getAbsolutePath());
and then start Fuseki:
FusekiCmd.main(
"--update",
"--loc=" + getAbsolutePath(),
"/mydataset");
so you are starting Fuseki inside another JVM process?
You can not reliably access the same database from inside and outside
Fuseki in the version you are using. (Actually, I have no idea if it's
safe or not).
I never access the database from TDB directly,
then why are you opening it in the first code snippet above? Fuseki
opens the database. No other code must do so.
(32 or 64 bit JVM? Which OS?)
but always by Fuseki.
I try to do the same operation using Fuseki 0.2.5 and TDB 0.9.4 and I don't
have this problem of null resource in triples, so I think was a bug of the
versions I'm using.
I can't upgrade Fuseki or TDB because I use them in a project that still
use jena, arq and so on and the library required by Fuseki but 'cause of
compatibility versions problem I can't upgrade them (I know, it's a boring
problem).
Which library? Maybe porting the current codebase, or 0.2.5 codebase,
is an option.
The differences between 0.2.5 and 0.2.4 aren't going to be very large.
So, concluding, can I do something (using Fuseki) to "force" the dataset to
synchronize data and persist them? (I think the problem could be this)
You haven't said what operation you can calling to update the data.
SPARQL Update? File upload? PUT or POST an RDF file?
Andy
Thanks a lot
Regards
Davide
2013/8/27 Andy Seaborne <[email protected]>
On 27/08/13 19:25, Rob Vesse wrote:
But If I
stop the JVM of my Fuseki server (and TDB) from my IDE console, restart
it
and then query the dataset, the query returns to me null values for some
elements of some triples.
How do you stop the JVM? Also what is your TDB setup?
This sounds like one of two things:
1 - Dataset corruption possibly caused by non-graceful shutdown of the
server, once the dataset is corrupted you typically need to start afresh.
2 - Your TDB dataset is not persistent (are you using the --memTDB
option?)
Usually dataset corruption would be indicated by error messages in the
logs so if you didn't see those I would lean more towards it being option
2
Rob
Why can't you upgrade? Fuseki is a standalone. I hope you are not
accessing the database from TDB directly at the same time that Fuseki is
running. That will corrupt the data.
Andy
On 8/27/13 11:08 AM, "Davide Rossi" <[email protected]> wrote:
Hi everyone,
I'm using Fuseki 0.2.4 with TDB 0.9.3 (I know that are old version, but
unfortunately I can't change to another version). The problem is the
seguent: I write triples using Fuseki, than I query the dataset (using
Fuseku, of course) and the query returns all values correctly. But If I
stop the JVM of my Fuseki server (and TDB) from my IDE console, restart
it
and then query the dataset, the query returns to me null values for some
elements of some triples.
My question is: is this a bug of TDB or Fuseki version I'm using (I
thinks
TDB can't persist all inserted data) and than solved in new versions ? If
is not, can I do something to solve it?
Thanks a lot
Regards
Davide
