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can be managed without affecting the access to logical storage structures.
6 The section contains the following topics:
Overview of Oracle Grid Architecture
Overview of Application Architecture
Overview of Physical Database Structures
Overview of Logical Database Structures
Overview of Schemas and Common Schema Objects
Overview of the Oracle Data Dictionary
Overview of the Oracle Instance
Overview of Accessing the Database
Overview of Oracle Utilities
本节包含以下主题：
Oracle 网格体系结构概述
应用体系结构概述
物理数据库结构概述
逻辑数据库结构概述
方案及常用的方案对象概述
Oracle 数据字典概述
Oracle 实例概述
数据库访问概述
Oracle 工具概述
7 Overview of Oracle Grid Architecture 1.1.1 Oracle 网格体系结构概述
8 Grid computing is a new IT architecture that produces more resilient and
lower cost enterprise information systems. With grid computing, groups
of independent, modular hardware and software components can be connected
and rejoined on demand to meet the changing needs of businesses.
网格是新出现的 IT 体系结构，它可以提供更有弹性、成本更低的企业信息系统。
在网格中，众多独立的、模块化的软硬件组件可以随时地被联接和重组，以满足
业务 及业务变化的需要。
9 The grid style of computing aims to solve some common problems with
enterprise IT: the problem of application silos that lead to under
utilized, dedicated hardware resources, the problem of monolithic,
unwieldy systems that are expensive to maintain and difficult to change,
and the problem of fragmented and disintegrated information that cannot
be fully exploited by the enterprise as a whole.
网格形式的计算系统是为了解决企业 IT 中的常见问题：由不同的应用系统独占
硬件资源而导致的资源利用率低下；系统过于庞大而导致的难以 改进、维护昂
贵；信息过于分散而导致的企业信息难以作为整体充分利用。
10 Benefits of Grid Computing Compared to other models of computing, IT
systems designed and implemented in the grid style deliver higher quality
of service, lower cost, and greater flexibility. Higher quality of service
results from having no single point of failure, a robust security
网格的优势 和其他体系结构相比，基于网格设计、实施的 IT 系统能够提供更
高质量的服务，更低的成本，更大的灵活性。更高质量的服务来源于网格不存在
单点脆弱性（single point of failure），健壮的安全基础结构，和基于策略
的集中化管理方式。更低成本来源于软硬件资源利用水平的提高和管理、维护成
