Export all the objects of system tablespace and blow the tablespace and recreate the tablespace with one datafile. This is how you do for your database tablespaces. As it is SYSTEM tablespace there is inherent risk of this procedure might not work.
You can try if you have a test database. You can try on even production if you have solid recovery plan if something goes wrong.
Other alternative is build the tablespace on a different server with the same OS and Patch level and Oracle version and plug it in with current production. I did once for data tablespace like this not for system tablespace.
It scares me to give advise to play with system tablespace. What if when I attempt to do it on production. I can't think about it.
Recreating the whole database is the only option here. Usualy in system TS there are only SYS's objects, and you can not possibly export those. So the only option is to:
1. do a full export (not because of the SYSTEM tablespace's objects, but because of all the other objects),
2. drop the whole database,
3. freshly create the new database with appropriate system's datafile
4. perform a full import to restore non-system TS objects
Jurij Modic ASCII a stupid question, get a stupid ANSI
24 hours in a day .... 24 beer in a case .... coincidence?
Even if it is possible by any manipulations etc, it is of no use, as Oracle does not support dropping of datafiles, if use offline drop command and remove files from OS, next time if u start oracle, it shall not .
Dropping datafile is OUT OF CONTEXT here, as one shouldn't attempt to do it no matter what the situation. Anybody could tell me the reason why Oracle provided that stupid option for DBA's. One always tempted to that and endup in soup.
Oracle says, drop datafile if you have the intention of dropping tablespace. CRAZY ! If I have the intention of dropping tablspace, I will drop tablespace and then remove files at OS level, why do I go and drop datafiles one by one and blow tablespace at the end... Doesn't make sense to have this option at all and the reason Oracle giving to provide that option...
I have seen co-dba burning his hands by doing this once and we end up staying at work with no sleep for 36 hours.