Oracle Database Discussions

Hi there.

It's Oracle 10g and I'm trying to specify a max size to the UNDO tablespace by using the following line in dbc file to a specific database instance while creating it:

<Name id="2" Tablespace="UNDOTBS1" Contents="UNDO" Size="25" maxsize="2G" autoextend="true" blocksize="8192">{SYSTEM_DG}/oradata

The issue is that I have another databases instances which were created prior to this one and without a maxsize keyword on its UNDO tablespace specification. All of them shared the same UNDO tablespace. So, as I undestand, the UNDO tablespace may be shared among various databases instances. Please correct me here if I'm wrong here.

Based on this context, my question is: If I have created databases instances without the maxsize keyword in their dbc files, must I have to recreate all the database instances again to limit the this UNDO tablespace size?

I've tested the creation of a new database instance using the mentioned line to specify the tablespace but nothing has changed regarding the maxsize. It remains with the default maxsize of 32GB:

Status Aut Name Type Extent Man Size (M) Max Size (M) Used (M) Used % Used % (Max)
ONLINE YES UNDOTBS1 UNDO LOCAL 190.000 32,767.984 24.438 12.86 0.07

Just to complement, I do have the following lines in my dbc file regarding the UNDO:

(...)
<initParam name="undo_management" value="AUTO"/>
<initParam name="undo_tablespace" value="UNDOTBS1"/>
(...)

Due to some enviroment restrictions, I cannot remove all the databases to see if it could work. Even so, I must be sure if setting the maxsize over all the .dbc files would limit the tablespace size. This way the database admins who are going to reinstall the databases at the production site will be sure of the solution prior the stop time.

One idea is to recreate this instance by specifying another tablespace name and datafile. I'm going to do that and report the results.

Hope to hear something from you guys.

Thanks in advance,
Fred