Tham khảo sách 'less17_flashback_tb3', công nghệ thông tin, cơ sở dữ liệu phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Performing Flashback Objectives After completing this lesson, you should be able to: Describe Flashback Database Restore the table content to a specific point in the past with Flashback Table Recover from a dropped table View the contents of the database as of any single point in time with Flashback Query See versions of a row over time with Flashback Versions Query View transaction history or a row with Flashback Transaction Query Flashback Technology: Benefits The Flashback technology is a revolutionary advance in recovery. Traditional recovery techniques are slow. The entire database or a file (not just the incorrect data) has to be restored. Every change in the database log must be examined. Flashback is fast. Changes are indexed by row and by transaction. Only the changed data is restored. Flashback commands are easy. No complex multiple-step procedures are involved. > Overview Database Table Drop Query Versions Transaction Flashback Technology: Benefits The Oracle Database 10g . | Performing Flashback Objectives After completing this lesson, you should be able to: Describe Flashback Database Restore the table content to a specific point in the past with Flashback Table Recover from a dropped table View the contents of the database as of any single point in time with Flashback Query See versions of a row over time with Flashback Versions Query View transaction history or a row with Flashback Transaction Query Flashback Technology: Benefits The Flashback technology is a revolutionary advance in recovery. Traditional recovery techniques are slow. The entire database or a file (not just the incorrect data) has to be restored. Every change in the database log must be examined. Flashback is fast. Changes are indexed by row and by transaction. Only the changed data is restored. Flashback commands are easy. No complex multiple-step procedures are involved. > Overview Database Table Drop Query Versions Transaction Flashback Technology: Benefits The Oracle Database 10g architecture leverages the unique technological advances in the area of database recovery from the loss of data due to human errors. The Flashback technology provides a set of new features to view and rewind data back and forth in time. The Flashback technology revolutionizes recovery by simply operating on the changed data. The time it takes to recover from the error is equal to the amount of time it takes to make the error. When applicable, the Flashback technology provides significant benefits over media recovery in terms of ease of use, availability, and restoration time. When to Use the Flashback Technology Object Level Scenario Examples Flashback Technology Uses Affects Data Database Truncate table; Undesired multitable changes made Database Flashback logs True Table Drop table Drop Recycle bin True Update with the wrong WHERE clause Table Undo data True Compare current data with data from the past Query Undo data False Compare versions of a row Version Undo data False Tx .
