With the ever-increasing volume of data, there is an urgent need to provide expressive and efficient tools to support Big Data analytics. The declarative logical language Datalog has proven very effective at expressing concisely graph, machine learning, and knowledge discovery applications via recursive queries. In this demonstration, we develop Logic Library (LLib), a library of recursive algorithms written in Datalog that can be executed in BigDatalog, a Datalog engine on top of Apache Spark developed by us. LLib encapsulates complex logic-based algorithms into high-level APIs, which simplify the development and provide a unified interface akin to the one of Spark MLlib. As LLib is fully compatible with DataFrame, it enables the integrated utilization of its built-in applications and new Datalog queries with existing Spark functions, such as those provided by \mlib and Spark SQL. With a variety of examples, we will (i) show how to write programs with LLib to express a variety of applications; (ii) illustrate its user experience in Apache Spark ecosystem; and (iii) present a user-friendly interface to interact with the LLib framework and monitor the query results.

Demand for powerful, high-performance analytics on large Data Bases has been ever growing. Database Management Systems have long shown that descriptive analytics can be supported quite effectively by enriching traditional aggregates with constructs such as Data Cubes and other ROLAPs - thus extending the optimizability and parallelizability of RDBMS. In this paper, we show that these benefits can now be extended to predictive analytics, e.g. clustering, classification and association, by using aggregates in declarative recursive queries. Therefore, we introduce KDDLog, a scalable framework which leverages recursive queries with aggregates and our newly-proposed chain aggregates to enable users to build or customize knowledge discovery models with concise and expressive queries. We further propose specialized compilation techniques for semi-naive fix-point computation in the presence of aggregates, and optimizations for complex recursive queries on distributed data platforms. We provide KDDLib to build knowledge discovery tasks and advanced interfaces to ease users of porting new models. Extensive evaluations on large-scale datasets demonstrate that our approach achieves promising performance gain while offering both increased generality and ease of programming knowledge discovery applications.

Many Data-Intensive Scalable Computing (DISC) Systems provide easy-to-use functional APIs, and efficient scheduling and execution strategies allowing users to build concise data-parallel programs. In these systems, data transformations are concealed by exposed APIs, and intermediate execution states are masked under dataflow transitions. Consequently, many crucial features and optimizations (e.g., debugging, data provenance, runtime skew detection), which require runtime datafow states, are not well-supported. Inspired by our experience in implementing features and optimizations over DISC systems, we present SEIZE, a unified framework that enables dataflow inspection-wiretapping the data-path with listening logic-in MapReduce-style programming model. We generalize our lessons learned by providing a set of primitives defining dataflow inspection, orchestration options for different inspection granularities, and operator decomposition and dataflow punctuation strategy for dataflow intervention. We demonstrate the generality and flexibility of the approach by deploying SEIZE in both Apache Spark and Apache Flink, and by implementing a prototype runtime query optimizer for Spark. Our experiments show that, the overhead introduced by the inspection logic is most of the time negligible (less than 5 percent in Spark and 10 percent in Flink).

In Data-Intensive Scalable Computing (DISC) Systems, data transformations are concealed by exposed APIs, and intermediate execution moments are masked under dataflow transitions. Consequently, many crucial features and optimizations (e.g., debugging, data provenance, runtime skew detection) are not well-supported. Inspired by our experience in implementing features and optimizations over DISC systems, we present SEIZE, a unified framework that enables dataflow inspection- wiretapping the data-path with listening logic -in MapReduce-style programming model. We generalize our lessons learned by providing a set of primitives defining dataflow inspection, orchestration options for different inspection granularities, and operator decomposition and dataflow puncutation strategy for dataflow intervention. We demonstrate the generality and flexibility of the approach by deploying SEIZE in both Apache Spark and Apache Flink. Our experiments show that, the overhead introduced by the inspection logic is most of the time negligible (less than 5% in Spark and 10% in Flink).

Many Data-Intensive Scalable Computing (DISC) systems do not support sophisticated cost-based query optimizers because they lack the necessary data statistics. Consequently many crucial optimizations, such as join order and plan selection, are not well supported in DISC systems. RIOS is a Runtime Integrated Optimizer for Spark that lazily binds to execution plans at runtime, after collecting the statistics needed to make more optimal decisions. We evaluate the efficacy of our approach and show that better plans can be derived at runtime, achieving more than an order-of-magnitude performance improvement compared to compile time generated plans produced by the Apache Spark rule-base optimizer.