[Colloquium] Reminder: Liu/MS Presentation/Jun 4, 2019

[Margaret Jaffey]

This is a reminder about Chunwei Liu's MS Presentation tomorrow.

------------------------------------------------------------------------------
Date:  Tuesday, June 4, 2019

Time:  10:00 AM

Place:  John Crerar Library 298

M.S. Candidate:  Chunwei Liu

M.S. Paper Title: Mostly Order Preserving Dictionaries

Abstract:
Dictionary encoding, or domain encoding, is an important form of
compression that uses a bijective mapping to replace attributes from a
large domain (i.e. strings) with a finite domain (i.e. 32 bit
integers). This encoding both reduces data storage and allows for more
efficient query execution. Traditional dictionary encoding only
supports efficient equality queries, while range queries require that
encoded values are decoded for evaluating the predicates. An order
preserving dictionary allows for range queries without decoding by
ensuring that encoded keys follow the same order as the values in the
dictionary. While this approach enables efficient queries it requires
that the full set of values is known to create the mappings. In this
work we bridge this gap by introducing mostly ordered dictionaries
that use a best effort dictionary generation based on sampling the
input dataset. Query evaluation on a mostly ordered dictionary avoids
decoding when possible and gracefully degrades performance as the
ratio of ordered values decreases.

Chunwei's advisor is Prof. Aaron Elmore

Login to the Computer Science Department website for details:
 https://newtraell.cs.uchicago.edu/phd/ms_announcements#chunwei

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Margaret P. Jaffey            margaret at cs.uchicago.edu
Department of Computer Science
Student Support Rep (Ry 156)               (773) 702-6011
The University of Chicago      http://www.cs.uchicago.edu
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=