GraphDB FAQ

compared with
Key
This line was removed.
This word was removed. This word was added.
This line was added.

Changes (20)

View Page History
h5. Why does my repository report a different number of explicit statements with different rule sets?

Each rule set defines both rules and some schema statements, otherwise known as axiomatic triples. These (read-only) triples are inserted in to the repository at intialisation time and count towards the total number of reported 'explicit' triples. The variation may be up to the order of hundreds depending upon the rule set.

h5. Why can't I delete some statements?

Statements that were added during repository initialisation, either because they are asserted in rule files or because they were loaded using the "imports" parameter are marked read-only. Having read-only statements (especially schema definition statements) are is one way to ensure that 'smooth delete' can operate very quickly.

{note}GraphDB-SE does now allow read-only/schema statements to be modified when the repository is in a special mode. This feature will allow fast delete operations at the same time as ensuring that schemas can be changed when necessary. Full details on how to do this can be found in the [GraphDB-SE user guide|GraphDB-SE Reasoner#Schemaupdatetransactions] .
{note}

h5. Why won't Sesame start in Tomcat?

This problem will manifest itself in many ways after deploying the Sesame/GraphDB war files to the Tomcat's webapps directory. If you are unable to set the server URL in the Workbench, then this it is an indication that the this problem has occurred. It will likely be due to a permissions problem on the logging directory for the openrdf-sesame server. To check this, point your browser directly at the Sesame server with a URL similar to the following:

{noformat}
If you receive a stack trace containing the following:


bq. Invocation of init method failed; nested exception is java.io.IOException: Unable to create logging directory /usr/share/tomcat6/.aduna/openrdf-sesame/logs
then this indicates that Tomcat does not have write permission to its data directory (where it stores configuration, logs, and actual repository data). To fix this, log in as root to the server machine and do the following:

{noformat}
{noformat}

Now when you use the server URL in your browser, you should see the Sesame server welcome screen.


h5. Sesame Workbench starts, but gives a memory error on the 'explore' and 'query' menus

The maximum heap space must be increased, i.e. Tomcat's Java virtual machine must be allowed to allocate more memory. This can be done by setting the environment variable 'CATALINA_OPTS' to include the desired value, e.g. \-Xmx1024m

h5. I cannot copy GraphDB or 3rd party jars files to the openrdf-sesame WEB-INF/lib directory.

h5. Can not copy GraphDB or 3rd party jars files the openrdf-sesame WEB-INF/lib directory.

This directory will not exist until the Sesame war files have been deployed to the \[WEBAPPS\] directory AND Tomcat is running. If the war files have been deployed, but the directory does not exist, try restarting Tomcat.

h5. Can not I cannot connect the Sesame console to the local Sesame server at [http://localhost:8080/openrdf-sesame].

Make sure that the Sesame war files have been deployed and that Tomcat is running. Restart Tomcat if necessary.

h5. Can not create an GraphDB repository using the Sesame console
h5. I cannot create a GraphDB repository using the Sesame console.

Make sure that the repository template file(s) have been copied to the 'templates' sub-directory of the Sesame console's data directory. These files are:
* GraphDB-Enterprise - {{master.ttl}} and {{worker.ttl}}

h5. Can not create an GraphDB repository, the Sesame console says 'unknown Sail type'
h5. I cannot create a GraphDB repository, the Sesame console says 'unknown Sail type'.

The Sesame console cannot find the GraphDB jar file. Make sure it was copied from the distribution zip file to the 'lib' sub-directory of the Sesame installation directory.

h5. Cannot I cannot use my custom rule file (pie file), an exception occurred.

To use custom rule files, GraphDB must be running in a Java Virtual Machine JVM that has access to the Java compiler. The easiest way to do this is to use the Java runtime from a Java Development Kit (JDK).


h1. Backup/restore/import/export