Showing papers by "Ramez Elmasri published in 1997"
Aalborg University1, James Cook University2, University of Texas at Arlington3, Iowa State University4, University of Bologna5, University of Illinois at Urbana–Champaign6, George Mason University7, Mercedes-Benz8, Microsoft9, Agricultural University of Athens10, University of Udine11, Concordia University12, Polytechnic University of Milan13, University of South Australia14, Indian Institutes of Technology15, University of California16, University of Arizona17, University of South Florida18, City University of New York19, Stanford University20
TL;DR: In this article, a wide range of concepts specific to and widely used within temporal databases are defined, and explanations of concepts as well as discussions of the adopted names are provided. But the definitions of concepts are not discussed.
Abstract: This document1 contains definitions of a wide range of concepts specific to and widely used within temporal databases. In addition to providing definitions, the document also includes explanations of concepts as well as discussions of the adopted names.
287 citations
Proceedings Article•
01 Jan 1997
1 citations
TL;DR: The archiving techniques allow temporal data and the MBT access structure to span magnetic disks and optical disks to minimize the overhead of the migration process by taking advantage of append–only nature of temporal databases, and gracefully handle object versions with very long time intervals.
Abstract: This paper describes a magnetic/optical access structure for append–only temporal databases. We formally define the properties of an access structure, called the MonotonicB+ -Tree (MBT), that is well suited for Write-Once Read Many optical disks. We present an insertion algorithm for the MBT that does not require splitting of index nodes and give the time analysis for this algorithm. We also describe a storage architecture where optical disks work in tandem with magnetic disks. Magnetic disks are used for storing current versions and recent past versions, whereas optical disks are dedicated for archiving older past versions. Our archiving techniques: (1) allow temporal data and the MBT access structure to span magnetic disks and optical disks; (2) minimize the overhead of the migration process by taking advantage of append–only nature of temporal databases; (3) gracefully handle object versions with very long time intervals so that the delay in the migration process is kept to minimum; and (4) ensure that no false magnetic or optical disk address lookup is performed during search operations by duplicating some closed versions on both magnetic and optical disks. To validate our claims for the efficiency of migration techniques, we analyze the performance of temporal access structures partitioned between magnetic and optical disks. We show that the migration process has a minimal effect on the search time. Our simulation identifies important parameters, and shows how they affect the performance of the temporal access structures. These include mean of version lifespan, block size, query time interval length, and total number of versions.