Oracle 11g Feature Read Only Tables.

In oracle database 11g you can alter individual tables
to be read only. When in read-only mode, you can’t
issue any DML statements against the table. 

SQL>alter table emp read only;

Table altered.

SQL> select table_name,read_only from user_tables
  2  where table_name='EMP';

TABLE_NAME  READ_ONLY
----------- ---------
EMP         YES

SQL>alter table emp read write;

Table altered.


SQL> select table_name,read_only from user_tables
  2  where table_name='EMP';


TABLE_NAME  READ_ONLY
----------- ---------
EMP         NO