QSQL2: Query language support for logic-based similarity conditions on probabilistic databases

ProQua is a new probabilistic database system which combines information retrieval concepts with database technologies. In contrast to other state-of-the-art probabilistic database systems ProQua supports logic-based and weighted similarity conditions within its query language by a generic similarity operator. In this work we introduce the ProQua query language QSQL2 by presenting its syntax, semantics and query capabilities. Furthermore, we briefly discuss the main components of ProQua.