Encyclopedia of Database Systems

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

Synopsis Structure

  • Phillip B. Gibbons
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_383

Synonyms

Synopsis

Definition

A synopsis structure for a dataset S is any summary of S whose size is substantively smaller than S. Formally, its size is at most O(|S|ε), where |S| is the size (in bytes) of S, for some constant ε < 1.

Key Points

Synopsis structures are small, often statistical summaries of a data set. The term serves as an umbrella for any summarization structure of sufficiently small size, such as random samples, histograms, wavelets, sketches, top-k summaries, etc.

Synopsis structures are most commonly used in conjunction with data streams. The goal is to construct, in one pass over the data stream, a synopsis structure that can be used to answer any query from a prespecified class of queries. That is, at any point, a user may pose a query Q on the data stream thus far, and a (typically approximate) answer to Qmust be produced using only the current synopsis structure. Two key advantages of using a synopsis structure to answer queries are that the space overhead is...

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Recommeded Reading

  1. 1.
    Gibbons PB, Matias Y. Synopsis data structures for massive data sets. DIMACS Series in Discrete Mathematics and Theoretical Computer Science: External Memory Algorithms. 1999.Google Scholar

Copyright information

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

Authors and Affiliations

  1. 1.Computer Science Department and the Electrical and Computer Engineering DepartmentCarnegie Mellon UniversityPittsburghUSA

Section editors and affiliations

  • Divesh Srivastava
    • 1
  1. 1.AT&T Labs - ResearchAT&TBedminsterUSA