1 创建测试表 用sys用户创建测试表 SQLgt; CREATE TABLE HR.ST (ID NUMBER, TIME DATE); Table created. SQLgt; INSERT INTO
1 创建测试表
用sys用户创建测试表
SQL> CREATE TABLE HR.ST (ID NUMBER, TIME DATE);
Table created.
SQL> INSERT INTO HR.ST SELECT ROWNUM, CREATED FROM DBA_OBJECTS;
50416 rows created.
SQL> commit;
Commit complete.
2 授权
SQL> grant execute on DBMS_REDEFINITION to hr;
Grant succeeded.
SQL> grant CREATE ANY TABLE, ALTER ANY TABLE, DROP ANY TABLE, LOCK ANY TABLE, SELECT ANY TABLE to hr;
Grant succeeded.
3 新建中间表(分区的表结构)
SQL> create table mid_st(id number primary key, time date) partition by range(time)
2 (
3 partition p1 values less than(to_date('2004-7-1', 'yyyy-mm-dd')),
4 partition p2 values less than(to_date('2005-1-1', 'yyyy-mm-dd')),
5 partition p3 values less than(to_date('2005-7-1', 'yyyy-mm-dd')),
6 partition p4 values less than(maxvalue)
7 );
Table created
4 验证
SQL> EXEC DBMS_REDEFINITION.CAN_REDEF_TABLE(user, 'ST', DBMS_REDEFINITION.CONS_USE_PK);
PL/SQL procedure successfully completed
5 在线重定义
SQL> EXEC DBMS_REDEFINITION.START_REDEF_TABLE(USER, 'ST', 'MID_ST');
PL/SQL procedure successfully completed
6 同步数据(可选)
如果在执行DBMS_REDEFINITION.START_REDEF_TABLE()过程和执行DBMS_REDEFINITION.FINISH_REDEF_TABLE()过程直接在重定义表上执行了大量的DML操作,那么可以选择执行一次或多次的SYNC_INTERIM_TABLE()过程,,以减少最后一步执行FINISH_REDEF_TABLE()过程时的锁定时间。
SQL> EXEC DBMS_REDEFINITION.SYNC_INTERIM_TABLE(USER, 'ST', 'MID_ST');
PL/SQL procedure successfully completed
7 结束重定义
SQL> EXEC DBMS_REDEFINITION.FINISH_REDEF_TABLE(USER, 'ST', 'MID_ST');
PL/SQL procedure successfully completed
8 查看分区结果
SQL> select a.table_name, a.partition_name from user_tab_partitions a;
TABLE_NAME PARTITION_NAME
------------------------------ ------------------------------
ST P1
ST P2
ST P3
ST P4
9 放弃在线重定义
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, 'st', 'mid_st')以放弃执行在线重定义。
10 常见问题
10.1 无主键
SQL> EXEC DBMS_REDEFINITION.CAN_REDEF_TABLE(user, 'ST', DBMS_REDEFINITION.CONS_USE_PK);
BEGIN DBMS_REDEFINITION.CAN_REDEF_TABLE(user, 'ST', DBMS_REDEFINITION.CONS_USE_PK); END;
*
ERROR at line 1:
ORA-12089: cannot online redefine table "HR"."ST" with no primary key
ORA-06512: at "SYS.DBMS_REDEFINITION", line 137
ORA-06512: at "SYS.DBMS_REDEFINITION", line 1478
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 st add constraint pk_t primary key(id);
Table altered.
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;
10.2 未授权
SQL> EXEC DBMS_REDEFINITION.START_REDEF_TABLE(USER, 'ST', 'MID_ST');
begin DBMS_REDEFINITION.START_REDEF_TABLE(USER, 'ST', 'MID_ST'); end;
ORA-01031: insufficient privileges
ORA-06512: at "SYS.DBMS_REDEFINITION", line 50
ORA-06512: at "SYS.DBMS_REDEFINITION", line 1343
ORA-06512: at line 2

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