Tài liệu Managing time in relational databases- P12 pdf
Tài liệu Managing time in relational databases- P12 pdf
... effective
time it affects. As a relationship between a point in time and a
period of time, the basic options are that the point in time can
be earlier than the period of time, within the period of time, ... will continue on, and will
update the database. In doing so, it will begin by preserving the
original state of the version or versions about to be changed,
doing this by wit...
Tài liệu Managing time in relational databases- P7 pdf
... effective time than assertion
time, we also present an in- line notation for single asserted
Managing Time in Relational Databases. Doi: 10.1016/B978-0-12-375041-9.00006-6
Copyright
#
2010 Elsevier Inc. ... integrity constraints in relational theory are entity
integrity, referential integrity and domain integrity. Entity integ-
rity insures that the object represented by a row...
Tài liệu Managing time in relational databases- P9 pdf
... against non-temporal
tables insert, update or delete individual rows representing objects,
transactions against asserted version tables insert into a period of
time, update within a period of time, ... their destinations or their origins.
Deferred assertions are the result of applying deferred trans-
actions to the database. Instead of holding on to maintenance
Part 3 DESIGNING, MAINTAINING...
Tài liệu Managing time in relational databases- P13 pdf
... than instances, is a relationship between two relational
Managing Time in Relational Databases. Doi: 10.1016/B978-0-12-375041-9.00011-X
Copyright
#
2010 Elsevier Inc. All rights of reproduction in ... par-
tially included in that timespan, those being the ones at the begin
and/or end of the timespan. This delete transaction carries out a
{split} transformation on the episode in...
Tài liệu Managing time in relational databases- P16 pdf
... available.
By internalizing these datasets within the production tables
whose data they contain, we eliminate the costs of managing
them, including the costs of recovering from mistakes made in
managing ... is currently
asserted as being currently in effect, this view also contains
one row per object. In addition, since, at every point in time,
the original table contains rows t...
Tài liệu Managing time in relational databases- P19 pdf
... thing to note here is that we get
to this starting point in the search of the index without doing a
scan. Our strategy is to get to the desired result using an index
with little or no scanning.
Once ... fil-
tering on effective begin date, the index will be scanned for the
356 Chapter 15 OPTIMIZING ASSERTED VERSIONING DATABASES
remaining criteria including assertion begin date. And the same...
Tài liệu Managing time in relational databases- P23 pdf
... query.
Components: external pipeline dataset, internalized pipeline dataset.
point in time
Mechanics: a time period whose begin date value, using the closed-open
representation of time periods, is one clock ... physically present in the table as of that point in
time. The contents of a semantic logfile of that table, as of that point in
time, are all those rows asserted on or...
Tài liệu Managing time in relational databases- P1 ppt
... data in which none of that is
necessary, a world in which all pipeline datasets are contained
in the single table that is their destination or their point of origin.
In this world, maintaining ... useful by integrating them into
larger patterns. But he has worked in the world of business IT for
his entire career. And in that world, theory is fine, but it must
xx
PREFACE
MANAGING...
Tài liệu Managing time in relational databases- P2 pptx
... Versioning
Asserted Versioning Framework (AVF)
xxii
PREFACE
row the query author is interested in, two of those components
being time periods that may or may not intersect in various
ways. Continuing ... management losing
faith in data warehouse projects. As these large projects fell
increasingly behind schedule and rose increasingly over budget—
something large projects tend to do—the...
Tài liệu Managing time in relational databases- P3 doc
... point
in time forward to the point in time we are interested in.
But the defining feature of reconstructable methods is not the
movement of data from off-line to on-line storage. The defining ... waiting for the data, and the decisions
delayed until the data becomes available. In an increasingly
fast-paced business world, the opportunity cost of delays in
accessing data is incre...