Conjunctive Regular Path Queries in Lightweight Description Logics

Conjunctive regular path queries are an expressive extension of the well-known class of conjunctive queries and have been extensively studied in the database community. Somewhat surprisingly, there has been little work aimed at using such queries in the context of description logic (DL) knowledge bases, and all existing results target expressive DLs, even though lightweight DLs are considered better-suited for data-intensive applications. This paper aims to bridge this gap by providing algorithms and tight complexity bounds for answering two-way conjunctive regular path queries over DL knowledge bases formulated in lightweight DLs of the DL-Lite and EL families.