ALTER FLASHBACK ARCHIVE

Purpose

Use the ALTER FLASHBACK ARCHIVE statement for these operations:

• Designate a flashback data archive as the default flashback data archive for the system

• Add a tablespace for use by the flashback data archive

• Change the quota of a tablespace used by the flashback data archive

• Remove a tablespace from use by the flashback data archive

• Change the retention period of the flashback data archive

• Purge the flashback data archive of old data that is no longer needed

Prerequisites

You must have the FLASHBACK ARCHIVE ADMINISTER system privilege to alter a flashback data archive in any way. You must also have appropriate privileges on the affected tablespaces to add, modify, or remove a flashback data archive tablespace.

Syntax

alter_flashback_archive::=

flashback_archive_quota::=

flashback_archive_retention::=

Semantics

flashback_archive

Specify the name of an existing flashback data archive.

SET DEFAULT

You must be logged in as SYSDBA to specify this clause. Use this clause to designate this flashback data archive as the default flashback data archive for the system. When a CREATE TABLE or ALTER TABLE statement specifies the flashback_archive_clause without specifying a flashback data archive name, the database uses the default flashback data archive to store data from that table.

This statement overrides any previous designation of a different flashback data archive as the default.

ADD TABLESPACE

Use this clause to add a tablespace to the flashback data archive. You can use the flashback_archive_quota clause to specify the amount of space that can be used by the flashback data archive in the new tablespace. If you omit that clause, then the flashback data archive has unlimited space in the newly added tablespace.

MODIFY TABLESPACE

Use this clause to change the tablespace quota of a tablespace already used by the flashback data archive.

REMOVE TABLESPACE

Use this clause to remove a tablespace from use by the flashback data archive. You cannot remove the last remaining tablespace used by the flashback data archive.

If the tablespace to be removed contains any data within the retention period of the flashback archive, then that data will be dropped as well. Therefore, you should move your data to another tablespace before removing the tablespace with this clause.

MODIFY RETENTION

Use this clause to change the retention period of the flashback data archive.

PURGE

Use this clause to purge data from the flashback data archive.

• Specify PURGE ALL to remove all data from the flashback data archive. This historical information can be retrieved using a flashback query only if the SCN or timestamp specified in the flashback query is within the undo retention duration.

• Specify PURGE BEFORE SCN to remove all data from the flashback data archive before the specified system change number.

• Specify PURGE BEFORE TIMESTAMP to remove all data from the flashback data archive before the specified timestamp.