3XL: An Efficient DBMS-Based Triple-Store

This paper demonstrates the use of 3XL, a DBMS-based triple-store for OWL Lite data. 3XL is characterized by its use of a database schema specialized for the data to represent. The specialized database schema uses object-relational features -- particularly inheritance -- and partitions the data such that it is fast to locate the needed data when it is queried. Further, the generated database schema is very intuitive and it is thus easy to integrate the OWL data with other kinds of data. 3XL offers performance comparable to the leading file-based triple-stores. We will demonstrate (1) how a specialized database schema is generated by 3XL based on an OWL ontology; (2) how triples are loaded, including how they pass through the 3XL system and how 3XL can be configured to fine-tune performance; and (3) how (simple and complex) queries can be expressed and how they are executed by 3XL.