Databases Reference
In-Depth Information
overlaps, along one or two temporal dimensions, among a set
of rows accessed by the query.
The origins of Asserted Versioning in computer science
research, in IT best practices, and in contributions from the
authors, are illustrated in
Figure 3.1
. Although deferred trans-
actions and deferred assertions are the mechanisms for the
internalization of several pipeline datasets, they are shown as
a separate item in
Figure 3.1
because of
their particular
importance.
Computer Science Research
In 2000, Dr. Rick Snodgrass stated that academics had publi-
shed, at that time, over 1500 articles on temporal data manage-
ment [2000, Snodgrass, xviii]. And over the last decade, much
additional work has been done. For our purposes, this work falls
into two categories: (i) research relevant to our task of designing
and building a method of temporal data management that works
with today's technology; and (ii) research on future directions
for the implementation of temporal functions in commercial
DBMSs, and for
the specification of
these functions
in
extensions to the current SQL standard.
Research on bi-temporality within the
computer science community
The development of versioning within
the IT community
Episodes as managed objects
Asserted
Versioning
The internalization of pipeline
datasets
The
authors'
own
work
Deferred transactions and deferred
assertions
Full encapsulation of transactions and
of temporal integrity constraints
Figure 3.1 The Origins of Asserted Versioning.
