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Each work however follows a different path to evaluate their proposed techniques. Despite the practical significance of optimizing UDF queries, UDFs have not been so far the focus of the database benchmarks. In this paper, we present UDFBench, a UDF-centric database benchmark based on real-world schema and data. We identify the core overheads in UDF query execution and design the UDFBench UDFs and queries to enable experimentation with these overheads, alone or in tandem with others. 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