add column to middle of 12c table

SQL*Plus: Release 12.1.0.1.0 Production on Mon Jan 13 22:55:03 2014

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Last Successful login time: Mon Jan 13 2014 22:46:01 -05:00

Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Advanced Analytics
and Real Application Testing options

SQL> set trimspool on
SQL> set numformat 99
SQL> column column_name format a2

SQL> create table tbl
  2  (
  3          m number,
  4          i number,
  5          l number,
  6          e number
  7  );

Table created.

SQL>
SQL> insert into tbl values ( 1, 1, 0, 0);

1 row created.

SQL> alter table tbl modify ( l invisible, e invisible );

Table altered.

SQL> alter table tbl add dd number;

Table altered.

SQL> alter table tbl modify ( l visible, e visible );

Table altered.

SQL> select * from tbl;

  M   I  DD   L   E
--- --- --- --- ---
  1   1       0   0

SQL> select column_name, column_id, hidden_column, segment_column_id, internal_column_id
  2  from user_tab_cols
  3  where table_name = 'TBL'
  4  order by column_id
  5  ;

CO COLUMN_ID HID SEGMENT_COLUMN_ID INTERNAL_COLUMN_ID
-- --------- --- ----------------- ------------------
M          1 NO                  1                  1
I          2 NO                  2                  2
DD         3 NO                  5                  5
L          4 NO                  3                  3
E          5 NO                  4                  4