temporal logo
 
Timestamp Representation
Curtis Dyreson, Assistant Prof., Washington State University
Fast I/O
Granularity
Indeterminacy
MultiCal
Now
TADT
Timestamps
TSQL2
 
Curtis Dyreson
  Home
  Publications
  Projects
  Software
  Demos
  Teaching
  Contact me

Publications

  • Curtis E. Dyreson and Richard T. Snodgrass. Timestamp Semantics and Representation. Information Systems, 18(3), 1993, pp. 143-166.
    PDF
  • Curtis E. Dyreson and Richard T. Snodgrass, A Timestamp Representation. In The TSQL2 Temporal Query Language. Richard T. Snodgrass, editor. Kluwer Academic Press, 1995. pp. 471-496.
    DBLP Electronic Edition

Abstract

Many database management systems and operating systems provide support for time values. At the physical level time values are known as timestamps. A timestamp has a physical realization and a temporal interpretation. The physical realization is a pattern of bits while the temporal interpretation is the meaning of each bit pattern, that is, the time each pattern represents. All previous proposals defined timestamps in terms of seconds. However, as we show, there are at least seven definitions of this fundamental time unit. We propose a more precise temporal interpretation, the time-line clock, that constructs a time-line by using different well-defined clocks in different periods. We also propose timestamp formats for events, intervals and spans. These formats can represent all of time to the granularity of a second, and all of recorded history to a finer granularity of a microsecond. Our proposed formats were designed to be more space and time efficient than existing representations. We compare our formats with those used in common operating systems and database management systems.
                                                                                                                                                                                                                                     
Curtis E. Dyreson © 1993-2001. All rights reserved.
  E-mail questions or comments to Curtis.Dyreson at usu.edu