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数据库介绍

Publié à 2024-05-02 23:06:56Vu 181 fois

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什么是数据库

狭义：储存数据的仓库

广义：可以对数据进行储存和管理的软件以及数据本身统称为数据库

数据库是由表，关系，操作组成

为什么需要数据库

几乎所有的应用软件的后台都需要数据库

数据库储存数据占用空间小，容易持久保存

储存比较安全

容易维护和升级

数据移植比较容易

简化对数据的操作

为将来学习Oracle做准备

B/S架构里面包含数据库

数据库应用软件

大型数据库：Oracle；DBI

中型数据库：SQL Server

小型数据库：MySQL

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