In case you have an error in your pom.xml like
Missing artifact com.oracle.jdbc:ojdbc6:jar:11.1.0.8.0 pom.xml /SandBox
Then you have to download the Oracle JDBC driver from Oracle and install the artifact into your local Maven repository with
mvn install:install-file -Dfile={path to your download directory}/ojdbc6.jar -DgroupId=com.oracle.jdbc -DartifactId=ojdbc6 -Dversion=11.1.0.6.0 -Dpackaging=jar