![]() For information about the GRANT statement, see Oracle Database SQL Language Reference.įor Oracle Flashback Query and Oracle Flashback Version Query You or your database administrator must grant privileges to users, roles, or applications that must use these flashback features. For more information, see "Using Flashback Data Archive (Oracle Total Recall)". Use Flashback Data Archive to automatically track and archive both regular queries and Oracle Flashback Query, ensuring SQL-level access to the versions of database objects without getting a snapshot-too-old error. (Flashback Transaction is part of DBMS_FLASHBACK package.) For more information, see "Using DBMS_FLASHBACK Package".įlashback Data Archive (Oracle Total Recall) This recovery operation uses undo data to create and run the corresponding compensating transactions that return the affected data to its original state. Use Flashback Transaction to roll back a transaction and its dependent transactions while the database remains online. For more information, see "Using DBMS_FLASHBACK Package". Use this feature to set the internal Oracle Database clock to an earlier time so that you can examine data that was current at that time, or to roll back a transaction and its dependent transactions while the database remains online (see Flashback Transaction). ![]() Typically, you use Oracle Flashback Transaction Query with an Oracle Flashback Version Query that provides the transaction IDs for the rows of interest (see "Using Oracle Flashback Transaction Query with Oracle Flashback Version Query"). ![]() For more information, see "Using Oracle Flashback Transaction Query". To perform an Oracle Flashback Transaction Query, select from the static data dictionary view FLASHBACK_TRANSACTION_QUERY. Use this feature to retrieve metadata and historical data for a given transaction or for all transactions in a given time interval. For more information, see "Using Oracle Flashback Version Query". To create an Oracle Flashback Version Query, use the VERSIONS BETWEEN clause of the SELECT statement. Metadata for each row version includes start and end time, type of change operation, and identity of the transaction that created the row version. Use this feature to retrieve metadata and historical data for a specific time interval (for example, to view all the rows of a table that ever existed during a given time interval). ![]() For more information, see "Using Oracle Flashback Query (SELECT AS OF)". Use this feature to retrieve data for an earlier time that you specify with the AS OF clause of the SELECT statement. (You can also use these features interactively as a database user or administrator.) In application development, you can use these flashback features to report historical data or undo erroneous changes. Recover terminated transactions by using database or process recoveryįor additional general information about flashback features, see Oracle Database Concepts Besides using it in flashback features, Oracle Database uses undo data to perform these actions: By using flashback features, you can use undo data to query past data or recover from logical damage. Undo data is persistent and survives a database shutdown. For example, if a user runs an UPDATE statement to change a salary from 1000 to 1100, then Oracle Database stores the value 1000 in the undo data. They rely on undo data, which are records of the effects of individual transactions. Oracle Flashback features use the Automatic Undo Management (AUM) system to obtain metadata and historical data for transactions. Roll back a transaction and its dependent transactions while the database remains online Recover tables or rows to a previous point in timeĪutomatically track and archive transactional data changes Perform queries that return metadata that shows a detailed history of changes to the database Oracle Flashback Technology is a group of Oracle Database features that let you view past states of database objects or to return database objects to a previous state without using point-in-time media recovery.
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