Table compression and alter table statement

Question

Friends
I am trying to add columns to a table which is compressed. Since Oracle treats compressed tables as Object tables, I cannot add columns directly so I tried to uncompress table first and then add columns. This doesnt seems to work.
What could be issue.
Thanks
Vishal V.
Script to test is here and results are below.
-- Test1 => add columns to uncompressed table -> Success
DROP TABLE TAB_COMP;
CREATE TABLE TAB_COMP(ID NUMBER) NOCOMPRESS;
ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10));
-- Test2 =. try adding columns to compressed tables, uncompress it and then try again -> Fails
DROP TABLE TAB_COMP;
CREATE TABLE TAB_COMP(ID NUMBER) COMPRESS;
ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10));
ALTER TABLE TAB_COMP move NOCOMPRESS;
ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10));
SQL> -- Test1 => add columns to uncompressed table -> Success
SQL> DROP TABLE TAB_COMP;
Table dropped.
SQL> CREATE TABLE TAB_COMP(ID NUMBER) NOCOMPRESS;
Table created.
SQL> ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10));
Table altered.
SQL>
SQL> -- Test2 =. try adding columns to compressed tables, uncompress it and then try again -> Fails
SQL> DROP TABLE TAB_COMP;
Table dropped.
SQL> CREATE TABLE TAB_COMP(ID NUMBER) COMPRESS;
Table created.
SQL> ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10));
ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10))
ERROR at line 1:
ORA-22856: cannot add columns to object tables
SQL> ALTER TABLE TAB_COMP move NOCOMPRESS;
Table altered.
SQL> ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10));
ALTER TABLE TAB_COMP ADD (NAME VARCHAR2(10))
ERROR at line 1:
ORA-22856: cannot add columns to object tables

Answer 1

Which version of oracle you are using?
1* create table test1234(a number) compress
SQL> /
Table created.
Elapsed: 00:00:00.02
SQL> alter table test1234 add(b varchar2(200));
Table altered.
Elapsed: 00:00:00.02