How do I get rid of undo tablespace offline?

How do I get rid of undo tablespace offline?

sql> select status,segment_name from dba_rollback_segs where status not in (“OFFLINE’) and tablespace_name=[undo tablespace to be dropped]; For example: sql> select status,segment_name from dba_rollback_segs where status not in (“OFFLINE’) and tablespace_name=’UNDOTBS1′;

How do I recover an undo tablespace?

In the case that you are not able to drop the undo tablespace, you can do the following.

1. Leave the old undo tablespace.
2. Shutdown the database and startup; then drop the undo tablespace.
3. Create a new control file remove all references to the old undo tablespace and run the script.

How do I turn on undo retention guarantee?

Setting the Undo Retention Period

1. Set UNDO_RETENTION in the initialization parameter file. UNDO_RETENTION = 1800.
2. Change UNDO_RETENTION at any time using the ALTER SYSTEM statement: ALTER SYSTEM SET UNDO_RETENTION = 2400;

Can we create undo tablespace in Mount state?

As the database is at mount, open it: SQL> alter database open; SQL> create undo tablespace undotbs1 datafile /u01/Oracle/oradata/undotbs01.

How do I undo a tablespace online?

Altering Undo Tablespace

1. Adding datafile. SQL> ALTER TABLESPACE undotbs ADD DATAFILE ‘/path/undo0102.dbf’ AUTOEXTEND ON NEXT 1M MAXSIZE UNLIMITED;
2. Renaming datafile.
3. Resizing datafile.
4. Making datafile online or offline.
5. Beginning or ending an open backup on datafile.
6. Enabling and disabling undo retention guarantee.

What is undo retention guarantee?

If retention guarantee is enabled, the specified minimum undo retention is guaranteed; the database never overwrites unexpired undo data even if it means that transactions fail due to lack of space in the undo tablespace.

How to make datafile online which in offline, recovery status on?

This note describes how to bring datafile online which in offline, recovery status in standby site. If standby datafile is marked offline and its status in controlfile shows “RECOVER”, it means , you can not make datafile back online without recovery. If you haven’t enough archived logs for recovery, you need restore datafile from primary database.

How to get data files back online after media recovery?

Bring All Data Files Online After Media Recovery is complete, some data files may be offline. Connect sys/password as sysdba in sqlplus and run the following query to find which datafiles are offline: Select file# from v$datafile where status = ’OFFLINE’; Note all file# numbers that are returned.

How to take data files out of backup?

Multiple commands can be used to take data files out of backup mode. While in sqlplus, connect to the database as sys/password as sysdba. Using the file numbers from the query above, take each file out of backup mode (this example assumes that datafiles 12 and 15 listed in v$backup):

Why are my data files not back online?

If there are any rows returned, note each file number (the first column data returned) to use later. If there are rows returned in the query from v$backup, then this means that the database crashed while there was a database backup running. To get the database back online, we need to take the files out of backup mode, and bring them online.