For some problems, human assistance is needed in addition to automated (algorithmic) computation. In sharp contrast to existing data management approaches, where human input is either ad-hoc or is never used, we describe the design of the first declarative language involving human-computable functions, standard relational operators, as well as algorithmic computation. We consider the challenges involved in optimizing queries posed in this language, in particular, the tradeoffs between

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... y, cost and performance, as well as combination of human and algorithmic evidence. We believe that the vision laid out in this paper can act as a roadmap for a new area of data management research where human computation is routinely used in data analytics.