An important aspect of planning ahead is the intelligent management of database data structures. For example, what can you do to prevent a database crash if your control file become corrupted? What can you do to prevent the loss of archived redo logs if a disk failure occurs? Besides the datafiles, the data structures that are most important for developing a backup and recovery strategy are: Control files Online redo logs Archived redo logs (if you run in ARCHIVELOG mode) If these structures become corrupted or unavailable, then you may find yourself unable to recover lost data. 导出导入只是逻辑备份，不是物理备份
导出导入只是逻辑备份，不是物理备份