Running QLever

In the following we assume that you want to run QLever on the knowledge base Fbeasy. To run on one of the other knowledge bases, replace fbeasy by freebase or wikidata in all the commands below.

NOTE: The Wikidata index for QLever needs 3 TB of Free disk memory.

• Download the corresponding index files (use the following command, alternatively they are linked on the main page).

  wget http://vldb2021-1807.hopto.org/qlever-fbeasy-index.tar.bz2
  

• Extract the index files

  tar xvjf qlever-fbeasy-index.tar.bz2
  

• Make the folder read- and writeable for everyone (you need at least read and write permissions for the Docker user) and enter it.

  chmod a+rwx qlever-fbeasy-index
  chmod a+rw qlever-fbeasy-index/*
  cd qlever-fbeasy-index
  

• Download and import the qlever-docker image.

  wget http://vldb2021-1807.hopto.org/qlever-docker.tar.bz2
  docker load --input qlever-docker.tar.bz2
  

  (In case you are interested in inspecting QLever's source code, follow the link on the main page)

• Run QLever inside Docker

  This assumes that you are running QLever on the local port 7001. If this port is not free on your machine, specify another port (replace the 7001 before the colon in the following command).

  docker run -d -p 7001:7001 -e "INDEX_PREFIX=fbeasy" -v "$(pwd):/index" --name qlever-fbeasy qlever.autocompletion.reproducibility
  

  QLever is now starting, this might take several minutes. You can monitor this process using docker logs

  docker logs -f qlever-fbeasy
  

  When the startup is finished, you should see the message "Waiting for Query on Port 7001" in the log.

  Check the accesibility of QLever by navigating to http://localhost:7001/?cmd=stats in a web browser (adapt to your changed port if necessary). You should receive a JSON result with statistics on the knowledge base. If this doesn't work, also try 172.17.0.1 (Docker's virtual network bridge) instead of localhost, depending on your Docker configuration.

• The QLever-Fbeasy instance is now ready. You can run the evaluation script as described in the respective tutorial.