Stack Overflow
Stack Overflow

Questions tagged [tdb]

TDB is an open source RDF database developed and maintained by the Apache Jena project

TDB is an open source RDF database developed and maintained by the Apache Jena project. It is a Java based embedded database that may be exposed over HTTP using the Fuseki Server also from the Apache Jena project.

Features

It's features includes the following:

  • Persisting RDF Triples or Quads
  • Full SPARQL execution
  • Write ahead logging to provide serializable transactions and fault tolerance

Scalability and Performance

TDB typically scales up to datasets of a few hundred million triples or quads.

Compared to commercial alternatives TDB is often less scalable compared primarily because while it is persisted to disk it is fundamentally designed as an in-memory database. It relays heavily on RAM caches and memory mapped files so scalability tends to be limited by machine RAM.

Also TDB does not have any option of a clustered mode so cannot be scaled horizontally without additional technologies (e.g. manually created replicas and load balancers)

TDB is typically included in the Berlin SPARQL Benchmark Results for those interested in comparative performance data.

137 questions
1
vote
1 answer

Configuring Jena Fuseki + inference and TDB?

I am new to Jenna TDB and Fuseki. I would like to load Lehigh University Benchmark (LUBM) data generated with their data generator (ver.1.7) in to Fuseki. This is about 400 .owl files. used the following Configuration file, that comes with Fuseki…
AR5HAM
  • 1,220
  • 11
  • 19
1
vote
1 answer

Loading N-quad (.nq) file using TDBloader (fuseki)?

I have a .nq file and I want to load it into a Fuseki triple store, but I get the following error: Exception in thread "main" org.apache.jena.atlas.AtlasException: java.nio.charset.MalformedInputException: Input length = 1 at…
Enayat
  • 3,904
  • 1
  • 33
  • 47
1
vote
0 answers

error in transaction in Sparql and jena tdb?

This is my jena code: package neww; import static com.hp.hpl.jena.query.ReadWrite.READ ; import static com.hp.hpl.jena.query.ReadWrite.WRITE ; import com.hp.hpl.jena.query.ReadWrite ; import com.hp.hpl.jena.query.Dataset ; import…
cooljohny
  • 656
  • 5
  • 13
  • 31
1
vote
1 answer

rrdf and local triple stores in R

I am using the rrdf package to use RDF data in R. The library seems really nice, but there is no information about the possibility of local triple stores, such as TDB. Is it possible to use them, as they are part of Jena? Are there…
Mulone
  • 3,603
  • 9
  • 47
  • 69
1
vote
2 answers

Is there a Sesame SAIL for Jena TDB?

Does anybody know of a Sesame SAIL implementation for the Jena TDB triple store? Even a beta version would be helpful to get started with. [EDIT] To satisfy whoever voted this question down for lack of research: I've queried the Jena archives,…
Ola
  • 21
  • 2
1
vote
1 answer

Failing to create first instance of Jena TDB

public void createDatabase(){ // Make a TDB-backed dataset String directory = "MyDatabases/ex1/" ; Dataset dataset = TDBFactory.createDataset(directory) ; dataset.begin(ReadWrite.READ) ; // Get model inside the…
Thomas Zammit
  • 23
  • 6
1
vote
1 answer

Using tdbloader.bat to upload a RDF file and querying using tdbquery.bat

I want to upload an RDF file using tdbloader.bat (C:\apache-jena-2.10.0\bat, in my case). My turtle file is located in C:\apache-jena-2.10.0, and is named test.ttl. What will be the command line to load the turtle file using tdbloader.bat? After it…
Som Sarkar
  • 289
  • 1
  • 5
  • 24
1
vote
1 answer

Synchronizing the change in OWL file with Jena TDB dataset

I am using JENA TDB to store a OWL file read as OntModel. The code for the same is : public static void initializeModel(){ dataset=TDBFactory.createDataset("Path/to/TDBDir"); Model b = dataset.getDefaultModel(); ontModel=…
Dibyanshu Jaiswal
  • 197
  • 10
1
vote
3 answers

Is it possible to concurrently write to the same Dataset file but to different named graphs (each thread writing to a different named graph)?

In Jena's TDB, it seems that data is organized by a "Dataset" (specified by a directory) which can contain multiple "named graphs". Regarding the concurrency policy to query such data, the only documentation I found related to concurrency is the…
zack
  • 335
  • 3
  • 13
1
vote
1 answer

Jena ARQ/TDB Query Optimization

I have a rather small graph containing roughly 500k triples. I've also generated the stats.opt file and running my code on a rather fast computer (quad core, 16gb ram, ssd drive.) But for the query I'm building with the help of the OP interface, it…
Daniel Gerber
  • 3,226
  • 3
  • 25
  • 32
0
votes
0 answers

Is there possible duplicated triples in TDB2?

I'm using Jena TDB2 and I loaded a TDB dataset. I want to know whether TDB will contain two same triples or the loaded triples had been deduplicated when it build the TDB database.
unstuck
  • 31
  • 3
0
votes
0 answers

How do you actually create new databases with apache jena tdb?

I an complete beginner regarding RDF Stores / Semantic Web so this is rather a basic question. In RDBMS or Neo4j you can create new database with "CREATE DATABASE"-Command. But how does it work with apache jena tdb? I couldn't find anything specific…
MichaelJones
  • 1
  • 1
0
votes
0 answers

Can't finish clearing TDB graph - JenaTransactionException: end() called for WRITE transaction without commit or abort having been called

I'm trying to clear a moderately large TDB graph, around 13 million triples, so I'm paginating the triples retrieval to avoid OutOfMemory issues. Here's my code: private void clearDataset() { int offset = 0; int page = 1; long…
vivss
  • 21
  • 1
  • 1
  • 5
0
votes
0 answers

How to start Fuseki server when we have already existing database?

I have Fuseki TDB database having size 53MB. I try to make it available on an endpoint by the command line utility ./fuseki-server --tdb2 --loc=/path/to/database /ds . The endpoint on localhost:3030 get started but on querying, it gives empty…
Khan
  • 95
  • 1
  • 8
0
votes
1 answer

Why is Jena tdb2.tdbquery optimization stuck on "Reorder/generic"

I am using apache-jena-4.5.0 and fuseki pretty much out-of-the-box. I had created a TDB2 dataset using fuseki, but now shut it off and using command-line utilities of jena on a Windows box inside a bash shell. My basic command is: java -cp "*"…
Paul Cuddihy
  • 477
  • 6
  • 12
1 2 3
…
9 10