Integrating semi-join-reducers into state-of-the-art query processors

Semi-join reducers were introduced in the late 1970s as a means to reduce the communication costs of distributed database systems. Subsequent work in the 1980s showed, however, that semi-join reducers are rarely beneficial for the distributed systems of that time. This paper shows that semi-join reducers can indeed be beneficial in modern client-server or middleware systems - either to reduce comm…