从Oracle 9i升级到10g两个方案可供选择:1、利用oracle提供的一个升级实用程序dbua(database upgrade assistant)直接将9i的数据库
从Oracle 9i升级到10g两个方案可供选择:
1、利用oracle提供的一个升级实用程序dbua(database upgrade assistant)直接将9i的数据库升级到10g.
2、新建一个10g的数据库,利用oracle的导入/导出(imp/exp)实用程序迁移数据
1.首先来讲第一种方案(用升级程序:dbua):
适合: 这种方案适宜于数据量比较大,用导入导出工具来迁移可能要花费很长时间的数据库.
方法: 用这种方案的话我们要在原来的数据库的机器上安装10g的软件,不安装10g的数据库.安装完10g的软件后,运行10g的数据库升级助手实用程序 dbua,然后通过此升级向导完成9ig到10g的升级过程.升级过程中, dbua会自动的将一些数据库的配置更改成适合10g的环境,如数据库参数设置,内存配置,sql,pl/sql引擎等和数据库管理,操作相关的软件的版本也会自动升级到10g.
优点:
(1)对于数据规模比较大的数据库而言,用这种方法升级是最快速的.
(2)保留原有数据库的物理结构(如数据文件,重做日志文件)和逻辑结构(表空间,用户,系统权限设置等),无需重新规划数据库.
风险: 这种方案存在一定的风险.虽然,10g的数据库升级助手实用程序dbua总体而言比较稳定,但是万一升级失败的话,原来的数据库就有可能使用不了,某些功能丢失,或运行不正常.所以在正式升级之前一定要先在测试库上先演练一下升级的所有过程,确认无误后才能在生产库上执行升级
IT成本:此种方案不需追加新的硬件投资.
dbua支持直接升级的数据库版本:
1、 oracle 8版本8.0.6
2、oracle 8i版本8.1.7
3、 oracle 9i版本9.0.1
4、oracle 9i版本9.2.0
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