hi there,

the TOOLS tablespace is created for you by default if you either 1) create a default database with your Oracle installation or 2) create a database with the Database Configuration Assistant (DBCA).

if you create a db with the DBCA, and you choose the option to 'Create a Script' instead of 'Create Now', you will see somewhere in those scripts (usually in the alterTablespace.sql script) the line:

ALTER USER SYSTEM DEFAULT TABLESPACE TOOLS;

this prevents the SYSTEM user from creating any more objects in the SYSTEM tablespace by accident. many 3rd party DBA tools will create a repository of some sort in the db. If you choose for the SYSTEM user for the owner of these tools, many of these repositories and other objects will be created in the SYSTEM tablespace by default. this is bad.

as you can see, the TOOLS tablespace allows for a default tablespace for inadvertent objects created by the SYSTEM user. Also, many people directly specify this tablespace for their DBA tools like OEM and such.

note that the existence and use of this TOOLS tablespace is not mandatory (as you obviously know, seeing how you don't have one). it is merely the Oracle installation default. it is recommended, however, to alter your SYSTEM user's default tablespace and temporary tablespace to one other than the SYSTEM tablespace.

have fun ,

nick