Oracle Database Administration/Undo Data

This lesson introduces Oracle database undo data.

Objectives and Skills
Objectives and skills for the undo data portion of Oracle Database Administration I certification include:
 * Managing Undo Data
 * Overview of Undo
 * Transactions and undo data
 * Managing undo

Readings

 * 1) Oracle: Database 2-Day DBA Managing Undo Data
 * 2) Oracle: Database Administrator's Guide Managing Undo

Multimedia

 * 1) YouTube: Managing Undo

Activities

 * 1) Complete the tutorial Oracle: Managing Database Storage Structures.
 * 2) View Undo storage.
 * 3) Use the following queries to view undo tablespaces and rollback segments:
 * 4) Use the following queries to view undo statistics:
 * 5) View transactions.
 * 6) Use the following query to begin a transaction:
 * 7) Use the following query to view transaction information:
 * 8) Open a second connection to the database and use the following query to select HR REGIONS:
 * 9) Use the following query in the first session to roll back the transaction:
 * 10) Use the following queries to verify the transaction was rolled back:
 * 11) Use Flashback.
 * 12) Use the following query to view HR REGIONS as of an hour ago:
 * 13) Use Enterprise Manager Database Control / Server / Automatic Undo Management / Edit Undo Retention to set the undo retention to 3600 seconds (1 hour).
 * 14) Use the following query to configure undo retention to 86400 seconds (1 day):
 * 15) Create undo tablespaces.
 * 16) Use Enterprise Manager Database Control / Server / Tablespaces to create an undo tablespace named UNDOTBS2 with a datafile named UNDOTBS02.
 * 17) Use the following query to identify the location of existing datafiles:
 * 18) Use the following query to create an undo tablespace:
 * 19) Manage undo tablespaces.
 * 20) Use Enterprise Manager Database Control / Server / Tablespaces to edit UNDOTBS2 and enable Undo Retention Guarantee.
 * 21) Use Enterprise Manager Database Control / Server / Automatic Undo Management to change the undo tablespace to UNDOTBS2.
 * 22) Use the following query to enable undo retention guarantee on UNDOTBS3:
 * 23) Use the following query to change the undo tablespace to UNDOTBS3:
 * 24) Delete undo tablespaces.
 * 25) Use Enterprise Manager Database Control / Server Automatic Undo Management and Tablespaces or the following queries to change the undo tablespace to UNDOTBS1 and delete the tablespaces UNDOTBS2 and UNDOTBS3: