... evaluating pattern queries. This algorithm was inspired by a standard imple-mentation for pattern matching over strings and its adap-tation in [26] as a basic execution model for event pattern matching. ... contrast,the backtrack algorithm, popular in pattern matching over strings and adapted in [26] for event pattern matching, eval-uates one run at a time and backtracks to evaluate other runswhen ... evaluation of pattern queries over streams. The pro-posed techniques, however, are tailored to various restrictedsets of pattern queries and pattern matching results, such aspatterns without...