数据泵与原始Imp、exp命令比较
- Data pump是一个服务器端的工具;数据泵可以实现暂停功能;
- imp、exp是一个客户端的工具;
Oracle Data Pump:Overview
As a server-based facility for high-speed data and metadata movement,Oracle Data Pump:
- Is callable via DBMS_DATAPUMP
- Provides the following tools
- expdp
- impdp
- Web-based interface
- Provides four data movement methods
- Data file copying
- Direct path
- External tables
- Network link support
- Detaches from and reattaches to long-running jobs
- Restarts Data Pump jobs
Oracle Data Pump:Benefits
Data Pump offers many benefits and some new features over earlier data movement tools ,such as:
- Fine-grained object and data selection
- 以前导出时可以按照表、用户等粒度进行导出，现如今可以更加细粒度导出
- 使用数据泵导出时，可以使用where条件进行更加细粒度的过滤
- Explicit specification of database version
- 导出时，可以指定兼容的数据库版本（11g的数据库中导出兼容10g的数据库的数据
- Estimation of exprot job space consumption(expdp功能可以，在真正导出之前，模拟一次导出，从而估算出需要的空间，来保障本地磁盘空间充足，足以满足本次导出操作.)
- Network mode in a distributed enviromment
- Remapping capabilities
- 将scott用户下的表，导出后，再倒入到test用户下，可以实现对象之间的映射
- Data sampling and metadata compression
- Compression of data during a Data Pump export
- Security through encryption
- Ability to export XML Type data as CLOBs
- Legacy mode to support old import and export files