I am new with Oracle Database and I want to know some command relate with Oracle.
Does anyone help me with below questions:
1. Which command use to show undo_retention period?
2. Which command use to show undo tablespace name?
3. how to disable/enable undo Retention guarantee?
Thanks,
- Which command use to show undo_retention period?
- Which command use to show undo tablespace name?
Open SQL*PLUS as SYSDBA
and use show parameter
command as shown below.
SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string AUTO
undo_retention integer 2400
undo_tablespace string UNDOTBS1
- how to disable/enable undo Retention guarantee?
Now you have the name of the undo tablespace.
Use the following command to switch to undo retention guarantee
.
ALTER TABLESPACE UNDOTBS1 RETENTION GUARANTEE;
To switch back to noguarantee
.
ALTER TABLESPACE UNDOTBS1 RETENTION NOGUARANTEE;
Use following query to check whether your undo tablespace has retention guaranteed or not.
SQL> SELECT tablespace_name, retention FROM dba_tablespaces where tablespace_name = 'UNDOTBS1';
For more details: Managing Undo