一本详细介绍硬盘各种参数的意义的书箱，适合计算机初学者看-A detailed descr iption of the significance of various parameters of the hard disk of the book box, look for computer beginners

基本导出方法： CREATE OR REPLACE DIRECTORY test_dir(directory别名) AS /u01/app/oracle/oradata/ (此处为硬盘上路径) GRANT READ, WRITE ON DIRECTORY test_dir(directory别名) TO scott(指定用户名)/public(所有用户) expdp scott/scott@orcl directory=test_ DUMPFILE=xx.dmp schem