ORA-01123

I was reading through an old book recently and it said that you could not put a tablespace into hot backup mode if the database was in NOARCHIVELOG mode. This seemed reasonable to me but I wondered what might happen if you tried to do this so I ran the following SQL in an Oracle 11.2 database:  

SQL> l

  1* alter tablespace users begin backup

SQL> /

alter tablespace users begin backup

*

ERROR at line 1:

ORA-01123: cannot start online backup; media recovery

not enabled

 

SQL>

If this happens to you, you have two choices:

•  Don't do it again OR
• Put the database into ARCHIVELOG mode first.

I hope to be doing some more serious posts about hot backup and recovery in the near future.