Cannot drop column from table owned by SYS

Question

Hello everybody,
How can I drop a column of table which is owned by sys? thanks!
Result as follows:
SQL> ALTER TABLE HELLO_TB DROP COLUMN NUM;
ALTER TABLE HELLO_TB DROP COLUMN NUM
ERROR at line 1:
ORA-12988: cannot drop column from table owned by SYS
newbie v

Answer 1

You can not 'change' the ownership.
You can, however, 'move' or 'clone' most objects by exporting and importing. As follows:
I create a table under SYS (shudder).
I then export it
- using userid SYS in this case,
- under normal circumstances I'd either use a DBA account or the owner's userid
- since I want a table, I use the TABLES option - a list is comma separated and in quotes
I then import it using a 'userid' switch - fromuser & touser options
- in this case from SYS to HR
Finally, I verify it was transported.
Actual console session in Linux follows:
pop2@fuzzy:~> sqlplus / as sysdba
SQL*Plus: Release 10.2.0.1.0 - Production on Fri Mar 10 19:58:01 2006
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> create table test1 ( x1 number );
Table created.
SQL> insert into test1 values (2);
1 row created.
SQL> select * from test1;
        X1
         2
SQL> Disconnected from Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
pop2@fuzzy:~> exp file=exp.dmp tables='TEST1'
Export: Release 10.2.0.1.0 - Production on Fri Mar 10 20:00:07 2006
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Username: sys/????? as sysdba
Connected to: Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
Export done in AL32UTF8 character set and AL16UTF16 NCHAR character set
About to export specified tables via Conventional Path ...
. . exporting table                          TEST1          1 rows exported
Export terminated successfully without warnings.
pop2@fuzzy:~> imp file=exp.dmp fromuser=sys touser=hr
Import: Release 10.2.0.1.0 - Production on Fri Mar 10 20:00:44 2006
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Username: sys/????? as sysdba
Connected to: Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
Export file created by EXPORT:V10.02.01 via conventional path
import done in AL32UTF8 character set and AL16UTF16 NCHAR character set
. importing SYS's objects into HR
. . importing table                        "TEST1"          1 rows imported
Import terminated successfully without warnings.
pop2@fuzzy:~> sqlplus hr/hr
SQL*Plus: Release 10.2.0.1.0 - Production on Fri Mar 10 20:00:57 2006
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> select * from test1;
        X1
         2
SQL>The export/import pair are incredibly powerful - and few people understand them well. If you are interested in digging into their capability, check out their chapters in the Utilities manual (under the Books tab) at http://www.oracle.com/pls/db102/portal.portal_db?selected=1