Oracle入门教程学习笔记
对于Oracle的学习与探讨,下面我是直接进行的,并没有对Oracle的历史进行讨论,因为在Oracle的官方有更好的解释,一下是我对Orac
对于Oracle的学习与探讨,下面我是直接进行的,并没有对Oracle的历史进行讨论,,因为在Oracle的官方有更好的解释,一下是我对Oracle知识的一个提炼
更多Oracle相关信息见Oracle 专题页面 ?tid=12
数据库基本概念: 数据库DB 数据库管理系统DBMS 数据库管理员DBA 数据模型
数据库DB
指以一定的组织方式存储在计算机存储设备上,能为多个用户所共享的与应用程序彼此独立相关数据的集合
它不仅包括描述事物的数据本身,而且还包括相关事物之间的关系
数据库管理系统DBMS
为数据库的建立,使用和维护而配置的软件,提供了安全性和完整性等统一控制机制
数据库管理系统一般具备数据库的定义、操作、查询及控制等功能
数据模型
用来描述世界中的事物及其联系,将数据库中的数据按照一定的结构组织起来,来反映事物本身及事物之间的各种联系
任何数据库管理系统都对应某种数据模型
1、层次型数据库
2、网状型数据库
3、关系型数据库(SQL Server)
4、对象关系型数据库(Oracle)
对象关系型数据库管理系统 ORDBMS Object Relationship Database Manager System
Oracle数据库的主要特点:
支持多用户、大事务量的事务处理
数据完全性和完整性控制
支持分布式数据处理
可移植性
Oracle服务器
Oracle服务器提供开发、全面和综合的信息管理,它由Oracle数据库和Oracle实例组成
Oracle服务器
Oracle数据库 Oracle实例
Oracle数据库:数据的集合,被视为一个逻辑单元
Oracle实例:管理数据库的后台进程和内存结构的集合

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