greg/stasis-aries-wal
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

cleanup of 2.2

Browse source
This commit is contained in:
Sears Russell 2006-04-23 21:33:51 +00:00
parent 5d769c5206
commit f73f124f2a
1 changed files with 15 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

29
doc/paper3/LLADD.tex
View file

@ -269,23 +269,24 @@ software we are interested in.
\subsection{The database abstraction} \subsection{The database abstraction}
Database systems are often thought of in terms of the high-level Database systems are often thought of in terms of the high-level
abstractions they present. For instance, Relational database systems abstractions they present. For instance, relational database systems
implement the relation model~\cite{cobb}, while object oriented implement the relational model~\cite{cobb}, object oriented
databases implement object abstractions, XML databases implement databases implement object abstractions, XML databases implement
hierarchical datasets, and so on. Before the relational model, hierarchical datasets, and so on. Before the relational model,
navigational databases implemented a navigational, pointer and record navigational databases implemented pointer and record
based data model. based data models.
An early survey of database implementations sought to enumerate the An early survey of database implementations sought to enumerate the
fundamental components used by database system implementors. This fundamental components used by database system implementors. This
survey was performed due to difficulties in extending database systems survey was performed due to difficulties in extending database systems
into new application domains. The survey divided databases into two into new application domains. The survey divided internal database
broad modules: conceptual mappings~\cite{batoryConceptual} and the routines into two broad modules: conceptual
physical database~\cite{batoryPhysical} model. mappings~\cite{batoryConceptual} and the physical
database~\cite{batoryPhysical} model.
A conceptual mapping may translate a relation into a set of keyed A conceptual mapping might translate a relation into a set of keyed
tuples. A physical model may translate a set of tuples into an tuples. A physical model could then translate a set of tuples into an
on-disk B-Tree with support for iterators and range-based query on-disk B-Tree, and provide support for iterators and range-based query
operations. operations.
It is the responsibility of a database implementor to choose a set of It is the responsibility of a database implementor to choose a set of
@ -298,10 +299,10 @@ top of it.
can support more than a small percentage of today's applications.} can support more than a small percentage of today's applications.}
Instead of attempting to create such a model after decades of database Instead of attempting to create such a model after decades of database
research has failed to produce one, we opt to provide a storage model research has failed to produce one, we opt to provide a transactional
that mimics the primitives provided by modern hardware as closely as storage model that mimics the primitives provided by modern hardware.
possible. This makes it easy for system designers to implement most This makes it easy for system designers to implement most of the data
of the data models that the underlying hardware can support. models that the underlying hardware is capable of supporting.
\subsection{\yad and ``traditional'' database workloads} \subsection{\yad and ``traditional'' database workloads}