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The constant growth of semantically-annotated data and an increasing interest in cross-domain knowledge bases raises the need for expressive query languages for RDF and novel approaches that enable their evaluation for web-scale data sizes. However, SPARQL, the W3C standard query language for RDF, suffers from a rather limited capability to express navigational queries. More expressive languages have been theoretically studied, however not implemented. In this paper, we continue our work on TRIAL-QL, an expressive (SQL-like) RDF query language based on the Triple Algebra with Recursion [31]. We present a new version of our TRIAL-QL processor, which takes advantage of the current momentum in in-memory SQL-on-Hadoop solutions and is built on top of Impala and SPARK while using one unified data storage. We use our system to study the application of multiple evaluation algorithms …