12C 数据库内归档 in-database archiving

12c中引入了in-database archiving的概念，就是对某个大表的部分数据进行标记为失效，数据库会对这些数据行进行压缩优化，但是这个操作对应用透明。标记之后这些数据在全表扫的时候就会直接忽略。
官方文档如下：
http://docs.oracle.com/cd/E16655_01/server.121/e17613/part_lifecycle.htm#VLDBG14154
简单测试：
修改参数，只显示表活动的数据行
SQL> ALTER SESSION SET ROW ARCHIVAL VISIBILITY = ACTIVE;

Session altered.

创建测试表row archival，并插入数据。
[code]SQL> create table row_arch_test (id number,name varchar2(10)) row archival;

Table created.

SQL> insert into row_arch_test values(1000,'Steven');

1 row created.

SQL> insert into row_arch_test values(2000,'Jobs');

1 row created.

SQL> SELECT SUBSTR(COLUMN_NAME,1,22) NAME, SUBSTR(DATA_TYPE,1,20) DATA_TYPE, COLUMN_ID AS COL_ID,
2 SEGMENT_COLUMN_ID AS SEG_COL_ID, INTERNAL_COLUMN_ID AS INT_COL_ID, HIDDEN_COLUMN, CHAR_LENGTH
3 FROM USER_TAB_COLS WHERE TABLE_NAME='ROW_ARCH_TEST';

NAME DATA_TYPE COL_ID SEG_COL_ID INT_COL_ID HID CHAR_LENGTH
---------------------- -------------------- ---------- ---------- ---------- --- -----------
ORA_ARCHIVE_STATE VARCHAR2 1 1 YES 4000
ID NUMBER 1 2 2 NO 0
NAME VARCHAR2 2 3 3 NO 10

SQL> select * from row_arch_test;

ID NAME
---------- ----------
1000 Steven
2000 Jobs

SQL> update row_arch_test set ORA_ARCHIVE_STATE='20' where ID=2000;

1 row updated.

SQL> select * from row_arch_test;

ID NAME
---------- ----------
1000 Steven

SQL> ALTER SESSION SET ROW ARCHIVAL VISIBILITY = ALL;

Session altered.

SQL> select * from row_arch_test;

ID NAME
---------- ----------
1000 Steven
2000 Jobs

SQL>[/code]