Oracle的在线重定义

Basic Steps for Manual Online Reorganization Commands and procedures used:
1.DBMS_REDEFINITION.CAN_REDEF_TABLE
2.CREATE TABLE …
3.DBMS_REDEFINITION.START_REDEF_TABLE
4.DBMS_REDEFINITION.COPY_TABLE_DEPENDENTS and DBMS_REDEFINITION.CONS_ORIG_PAGRAMS
SELECT object_name,base_table_name,ddl_txt FROM DBA_REDEFINITION_ERRORS;
6.DBMS_REDEFINITION.SYNC_INTERIM_TABLE
7.DBMS_REDEFINITION.FINISH_REDEF_TABLE
8.DROP TABLE ... PURGE

1.创建表

SQL> CREATE TABLE T (ID NUMBER PRIMARY KEY, TIME DATE);

2、插入数据

SQL> INSERT INTO T SELECT ROWNUM, CREATED FROM DBA_OBJECTS;
SQL> COMMIT;

3、在线重定义的表自行验证，看该表是否可以重定义

SQL> EXEC DBMS_REDEFINITION.CAN_REDEF_TABLE(user, 'T', DBMS_REDEFINITION.CONS_USE_PK);

（如果没有定义主键会提示以下错误信息）

begin dbms_redefinition.can_redef_table(user,'pft_party_profit_detail'); end;
ORA-12089: cannot online redefine table "OFSA"."PFT_PARTY_PROFIT_DETAIL" with no primary key
422ORA-06512: at "SYS.DBMS_REDEFINITION", line 8
ORA-06512: at "SYS.DBMS_REDEFINITION", line 247
ORA-06512: at line 1

出错了，该表上缺少主键，为该表建主键，再执行验证.

SQL> alter table t add constraint pk_t primary key(id);

Table altered.

4、建个和源表表结构一样的分区表，作为中间表。按日期范围分区

SQL> CREATE TABLE T_NEW
(ID NUMBER PRIMARY KEY, TIME DATE)
PARTITION BY RANGE (TIME)
(PARTITION P1 VALUES LESS THAN (TO_DATE('2004-7-1', 'YYYY-MM-DD')),
PARTITION P2 VALUES LESS THAN (TO_DATE('2005-1-1', 'YYYY-MM-DD')),
PARTITION P3 VALUES LESS THAN (TO_DATE('2005-7-1', 'YYYY-MM-DD')),
PARTITION P4 VALUES LESS THAN (MAXVALUE));

SQL> CREATE TABLE T_NEW (ID NUMBER PRIMARY KEY, TIME DATE)
PARTITION BY RANGE (TIME)
(PARTITION P20070201 VALUES LESS THAN (TO_DATE('2007-2-1', 'YYYY-MM-DD')),
PARTITION P20070301 VALUES LESS THAN (TO_DATE('2005-3-1', 'YYYY-MM-DD')),
PARTITION P20070401 VALUES LESS THAN (TO_DATE('2005-4-1', 'YYYY-MM-DD')),
PARTITION P20070501 VALUES LESS THAN (TO_DATE('2005-5-1', 'YYYY-MM-DD')),
PARTITION P20070601 VALUES LESS THAN (TO_DATE('2005-6-1', 'YYYY-MM-DD')));

5、执行表的在线重定义

SQL> EXEC DBMS_REDEFINITION.START_REDEF_TABLE(USER, 'T', 'T_NEW');

6、执行把中间表的内容和数据源表进行同步。

SQL>execute dbms_redefinition.sync_interim_table(user,'t','t_new');

7、执行结束在线定义过程。

SQL> EXEC DBMS_REDEFINITION.FINISH_REDEF_TABLE(user, 'T', 'T_NEW');

8、查看数据字典，可以看到改表已经成为了分区表

SQL> SELECT COUNT(*) FROM T;

COUNT(*)
----------
6264

SQL> SELECT COUNT(*) FROM T PARTITION (P2);

COUNT(*)
----------
6246

SQL> SELECT COUNT(*) FROM T PARTITION (P3);

COUNT(*)
----------

至此普通表转为分区操作完成。

9、如果执行在线重定义的过程中出错，可以在执行dbms_redefinition.start_redef_table之后到执行dbms_redefinition.finish_redef_table之前的时间里执行：DBMS_REDEFINITION.abort_redef_table(user, 't', 't_new')以放弃执行在线重定义.

10、如果出现以下错误

SQL> exec dbms_redefinition.can_redef_table(user, 't');

BEGIN dbms_redefinition.can_redef_table(user, 't'); END;

*

ERROR at line 1:

ORA-12091: cannot online redefine table "user"."t" with materialized views

ORA-06512: at "SYS.DBMS_REDEFINITION", line 137

ORA-06512: at "SYS.DBMS_REDEFINITION", line 1478

ORA-06512: at line 1

用这句删除materialized view 即可继续进行

drop materialized view log on ;

drop materialized view log on t;

OR

drop materialized t;