Accession Number : ADA189376

Title :   Aggregates in the Temporal Query Language TQuel,

Corporate Author : NORTH CAROLINA UNIV AT CHAPEL HILL DEPT OF COMPUTER SCIENCE

Personal Author(s) : Snodgrass, Richard ; Gomez, Santiago ; McKenize, Ed

PDF Url : ADA189376

Report Date : 27 Jul 1987

Pagination or Media Count : 53

Abstract : This paper defines aggregates in the temporal query language TQuel provides their formal semantics in the tuple relational calculus. A formal semantics for Quel aggregates is defined in the process. Multiple aggregates; aggregates appearing in the where, when, valid, and as-of clauses; nested aggregation; and instantaneous, cumulative, moving window, and unique variants are supported. These aggregates provide a rich set of statistical functions that range over time, while requiring minimal additions to TQuel and its semantics.

Descriptors :   *SEMANTICS, *PROGRAMMING LANGUAGES, *DATA MANAGEMENT, CALCULUS, MOTION, STATISTICS, VARIATIONS, WINDOWS, DATA BASES

Subject Categories : Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE