Encyclopedia of Database Systems

2018 Edition
| Editors: Ling Liu, M. Tamer Özsu

Crowd Database Systems

  • Ju FanEmail author
  • Meihui ZhangEmail author
  • Beng Chin OoiEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_80738


Crowd-powered database systems; Crowdsourcing data analytics systems; Declarative crowdsourcing systems; Human-powered database systems


Crowdsourcing database systems are designed to add crowd functionality into traditional database management systems (DBMSs) for processing queries that cannot be answered by machines only. The systems typically take declarative queries written in SQL-like query language as input and process over stored relational data together with the collective knowledge gathered on-demand from the crowd. A typical crowdsourcing database system includes a query parser, which compiles the input query; a query optimizer, which generates the optimized query plan; an executor, which manages the query execution; and an HIT manager, which interacts with the public crowd.

Historical Background

While relational database system offers a powerful tool for data management, it imposes limitations in some situations. One situation is when there is missing...

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Recommended Reading

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.DEKE Lab and School of InformationRenmin University of ChinaBeijingChina
  2. 2.Information Systems Technology and DesignSingapore University of Technology and DesignSingaporeSingapore
  3. 3.School of ComputingNational University of SingaporeSingaporeSingapore

Section editors and affiliations

  • Reynold Cheng
    • 1
  1. 1.Computer ScienceThe University of Hong KongHong KongChina