cleanup of 2.2

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Sears Russell 2006-04-23 21:33:51 +00:00
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@ -269,23 +269,24 @@ software we are interested in.
\subsection{The database abstraction}
Database systems are often thought of in terms of the high-level
abstractions they present. For instance, Relational database systems
implement the relation model~\cite{cobb}, while object oriented
abstractions they present. For instance, relational database systems
implement the relational model~\cite{cobb}, object oriented
databases implement object abstractions, XML databases implement
hierarchical datasets, and so on. Before the relational model,
navigational databases implemented a navigational, pointer and record
based data model.
navigational databases implemented pointer and record
based data models.
An early survey of database implementations sought to enumerate the
fundamental components used by database system implementors. This
survey was performed due to difficulties in extending database systems
into new application domains. The survey divided databases into two
broad modules: conceptual mappings~\cite{batoryConceptual} and the
physical database~\cite{batoryPhysical} model.
into new application domains. The survey divided internal database
routines into two broad modules: conceptual
mappings~\cite{batoryConceptual} and the physical
database~\cite{batoryPhysical} model.
A conceptual mapping may translate a relation into a set of keyed
tuples. A physical model may translate a set of tuples into an
on-disk B-Tree with support for iterators and range-based query
A conceptual mapping might translate a relation into a set of keyed
tuples. A physical model could then translate a set of tuples into an
on-disk B-Tree, and provide support for iterators and range-based query
operations.
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.}
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
that mimics the primitives provided by modern hardware as closely as
possible. This makes it easy for system designers to implement most
of the data models that the underlying hardware can support.
research has failed to produce one, we opt to provide a transactional
storage model that mimics the primitives provided by modern hardware.
This makes it easy for system designers to implement most of the data
models that the underlying hardware is capable of supporting.
\subsection{\yad and ``traditional'' database workloads}