Oracle Essentials [Electronic resources] : Oracle Database 10g, 3rd Edition نسخه متنی

Chapter 1. Introducing Oracle

Where do we start? One of the problems in comprehending a massive
product such as the
Oracle database is the difficulty of
getting a good sense of how the product works without getting lost in
the details of implementing specific solutions. This book aims to
solve this problem by giving you a thorough grounding in the concepts
and technologies that form the foundation of the Oracle Database
Server. Oracle also provides an Application Server and business
applications, including the E-Business Suite and the Oracle
Collaboration Suite,^[1] which are outside
the scope of the main body of this book.

^[1] Previous versions of this book
did cover iFS. In Oracle Database 10g, however,
this product is now known as Oracle Files and is now a part of the
Oracle Collaboration Suite. For this reason, iFS
is not covered in this edition.

We've tried to write a book for a wide range of
Oracle users, from the novice to the experienced user. To address
this range of users, we've focused on the concepts
and technology behind the Oracle database. Once you fully understand
these facets of the product, you'll be able to
handle the particulars of virtually any type of Oracle database.
Without this understanding, you may feel overburdened as you try to
connect the dots of Oracle's voluminous feature set
and documentation.

This first chapter lays the groundwork for the rest of the
discussions in this book. Of all the chapters, it covers the broadest
range of topics; most of these are discussed further later in the
book, but some of the basicsfor example, the brief history of
Oracle and the contents of the different
"flavors" of the Oracle database
productsare unique to this chapter.

Oracle has grown from its humble beginnings as one of a number of
databases available in the 1970s to the market leader of today. In
its early days, Oracle Corporation was known more as an aggressive
sales and promotion organization than a technology supplier. Over the
years, the Oracle database has grown in depth and quality, and its
technical capabilities now are generally recognized as the most
advanced. With each release, Oracle has added more power and features
to its already solid base while improving the manageability.

Several recent Oracle database releases are the focus of this book:

Oracle8i, released in 1999, added a new twist to
the Oracle databasea combination of enhancements that made the
Oracle8i database the focal point of the world
of Internet (the i in 8i)
computing.

Oracle9i, released in 2001, introduced Real
Application Clusters as a replacement for Oracle Parallel Server, and
added many management and data warehousing features.

Oracle Database 10g

Oracle Database 10g, released in 2003 and the current release,
enables grid (the g in 10g) computing. A
grid is simply a pool of computers that provides
needed resources for applications on an as-needed basis. The goal is
to provide computing resources that transparently scale to the user
community, much as an electrical utility company can deliver power to
meet peak demand by accessing energy from other power
providers' plants via a power grid. Oracle Database
10g further reduces the time, cost, and complexity of database
management through the introduction of self-managing features such as
the Automated Database Diagnostic Monitor, Automated Shared Memory
Tuning, Automated Storage Management, and Automated Disk Based Backup
and Recovery. One important key to Oracle Database
10g's usefulness in grid computing is the ability to
provision CPUs and data.

Before we dive into the specific foundations of these releases, we
must spend a little time describing some Oracle basicshow
databases evolved to arrive at the relational model, a brief history
of Oracle Corporation, and an introduction to the basic features and
configurations of the database.