Importing a Full Export

[jmodic]

I think you are messing things up when talking about "system".

About the "system" terminology:
1. SYSTEM is a name of tablespace, the tablespace that is created first during database creation and that contains database dictionary objects, which are owned by the user SYS. This is also the only tablespace that *must* be created in the database, all other tablespaces are optional (but of course, there is no production database on this planet with only this tablespace created ).
2. SYSTEM is also a name of the user that is usually created during database creation. This user is in fact not a particullarly "special" user, it is totaly ordinal user with DBA role. It is equivalent to any other user with simmilar privileges. In contrast, the user that realy is special is user SYS - this user is the owner of the database dictionary, the "heart" of the database.
3. "system" is also a word that is often used when refering to a database dictioanry or the core of the database

About the export in conjunction with "system":
Not that export never exports SYSTEM tablespace, it never exports *any* tablespace. Full export does export tablespace definitions (except for the deffinition of SYSTEM tablespace), but it doesn't export tablespaces in a sence "it will export all the segments from a particular tablespace". You can instruct export to export a particular tables or a particular users, but not to expoert a particular tablespace. It wouldn't be logical and it can't be done. When you do a full export, you will actually export all the users and their objects, no matter in which tablespace their objects reside, except for one user: SYS. None of SYS's objects will be exported, no matter if they are located in tablespace SYSTEM or any other tablespace.

About your $ objects in the export log:
This are realy not "system" tables, I mean they are not really a part of a datbase catalog. They are owned by user SYSTEM, not user SYS, that is why they are exported. Those tables are needed for some database options, in your case for advanced queuing and replication. As such they can be refered as a "kind of system" tables, so the question is why they are created in schema SYSTEM and not in schema SYS? There is only one, simple reason: becuse this way they can be exported! For those tables it is sometimes usefull if they can be exported and imported elsewhere, but for true dictionary tables owned by SYS Oracle does not (and must not) allow to be exported, es their import would corrupt the database totally.

As for deleting those SYSTEM.$ tables - yes, you can delete them without cousing database corruption, but the options they are required for will no longer work. So I wouldn't recomend to do so if you realy are using AQ or ttransaction replication.

I hope I haven't confused you even further ....

[anuragmin]

Thank you very much jurij, I really appreciate your help. This was indeed useful.

Now I need to refer to the manuals and first understand this concept thoroughly.

Regards
Anurag