复制数据库(DUPLICATE DATABASE)

技术限制

duplicate目前还不支持跨平台的复制，如windows <--> linux就是两个平台。复制的数据库和源库必须是相同的操作系统平台，我们认为同平台下的32-bit 和 64-bit是同一个平台，例如Linux IA (32-bit) 和Linux IA (64-bit)，认为是相同的平台，可以实施duplicate 功能，但是最后一定要运行脚本$ORACLE_HOME/rdbms/admin/utlirp.sql来转换成。
Typically, the source and duplicate databases must be on the same platform; however some cross-platform duplication is supported (1079563.1). For DUPLICATE, 32-bit and 64-bit versions of the same platform are considered the same platform. For example, Linux IA (32-bit) is considered the same platform as Linux IA (64-bit). However, after duplicating a database between 32-bit and 64-bit platforms, you must run the utlirp.sql script to convert the PL/SQL code to the new format. This script is located in ORACLE_HOME/rdbms/admin on Linux and UNIX platforms.

选择数据库复制技术

From active
              | with target connection
From backups  |                            | with catalog connection
              | without target connection  |
                                           | without catalog connection

具体复制技术实现见文。

文件名转换

有三种方法：

在 duplicate 的 run 块中进行路径转换外
在参数文件中通过 DB_FILE_NAME_CONVERT 和 LOG_FILE_NAME_CONVERT 进行路径转换
通过 duplicate database 中的 spfile 子句指定上面两个参数