欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  数据库

Oracle在线重定义DBMS_REDEFINITION 普通表—分区表

程序员文章站 2022-06-09 18:28:37
...

Oracle在线重定义DBMS_REDEFINITION 普通表mdash;gt;分区表

实验环境:RHEL 6.4 + Oracle 11.2.0.3
实验:在线重定义 普通表 为 分区表,包括主键对应的索引都改造为分区索引.

1,构造普通表t_objects


conn test1/test1;

create table t_objects as select * from dba_objects;

SQL> select count(1) from t_objects;

COUNT(1)

----------

468738

--t_objects建立主键和索引

alter table t_objects add constraint pk_objects primary key (created, object_id);

create index i_objects on t_objects(object_id, STATUS);

--表有主键,确认表可以重定义:

SQL> EXEC DBMS_REDEFINITION.CAN_REDEF_TABLE('test1','t_objects');

PL/SQL procedure successfully completed.

--若表无主键 可以采用rowid重定义:

SQL> EXEC DBMS_REDEFINITION.CAN_REDEF_TABLE('test1','t_objects',2);

PL/SQL procedure successfully completed.

2,创建重定义需要的临时表


-- Create table

create table T_OBJECTS_TEMP

(

OWNER VARCHAR2(30),

OBJECT_NAME VARCHAR2(128),

SUBOBJECT_NAME VARCHAR2(30),

OBJECT_ID NUMBER not null,

DATA_OBJECT_ID NUMBER,

OBJECT_TYPE VARCHAR2(19),

CREATED DATE not null,

LAST_DDL_TIME DATE,

TIMESTAMP VARCHAR2(19),

STATUS VARCHAR2(7),

TEMPORARY VARCHAR2(1),

GENERATED VARCHAR2(1),

SECONDARY VARCHAR2(1),

NAMESPACE NUMBER,

EDITION_NAME VARCHAR2(30)

)partition by range(created)(

partition P20130601 values less than (TO_DATE(' 2013-06-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIAN'))

tablespace DBS_D_GRNOPHQ,

partition P20140607 values less than (TO_DATE(' 2014-06-07 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIAN'))

tablespace DBS_D_GRNOPHQ,

partition P20140731 values less than (TO_DATE(' 2014-07-31 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIAN'))

tablespace DBS_D_GRNOPHQ

);


3,开始重定义

exec DBMS_REDEFINITION.START_REDEF_TABLE('test1','t_objects','t_objects_temp');

注;若无主键不能这样重定义,需要指定以rowid重定义,,示例如下:

SQL> exec DBMS_REDEFINITION.START_REDEF_TABLE('test1','t_objects','t_objects_temp',null,2);

PL/SQL procedure successfully completed.


4,开始拷贝表的属性(本次未做,因为这样转换的,索引不是分区索引)

DECLARE

error_count pls_integer := 0;

BEGIN

DBMS_REDEFINITION.COPY_TABLE_DEPENDENTS(

uname => 'test1',

orig_table => 't_objects',

int_table => 't_objects_temp',

ignore_errors => TRUE,

num_errors => error_count);

DBMS_OUTPUT.PUT_LINE('errors := ' || TO_CHAR(error_count));

END;

/

--经实验,在开始重定义之后在临时表上创建local索引,重定义完成后,主键对应的索引也是分区索引;

alter table t_objects_temp add constraint pk_objects_temp primary key (created, object_id) using index local;

create index i_objects_temp on t_objects_temp(object_id, STATUS) local;

5,同步数据

exec DBMS_REDEFINITION.SYNC_INTERIM_TABLE (uname => 'test1',orig_table => 't_objects',int_table => 't_objects_temp');

6,收集中间表的统计信息(选做)

EXEC DBMS_STATS.gather_table_stats('test1', 't_objects_temp', cascade => TRUE);

7,完成重定义

exec DBMS_REDEFINITION.FINISH_REDEF_TABLE(uname => 'test1',orig_table => 't_objects',int_table => 't_objects_temp');

EXEC DBMS_REDEFINITION.FINISH_REDEF_TABLE('TEST1','T_OBJECTS','T_OBJECTS_TEMP');

8,删除临时表

drop table t_objects_temp purge;

9,修改索引,约束名称和原表一致

alter index I_OBJECTS_TEMP rename to I_OBJECTS;

alter index PK_OBJECTS_TEMP rename to PK_OBJECTS;

alter table t_objects rename constraint pk_objects_temp to pk_objects;


10,ABORT_REDEF_TABLE使用

在FINISH_REDEF_TABLE之前,可以使用abort_redef_table停止重定义

SQL> select * from cat;

TABLE_NAME TABLE_TYPE

------------------------------ -----------

MLOG$_T_OBJECTS TABLE

T_OBJECTS TABLE

T_OBJECTS_TEMP TABLE

SQL> exec DBMS_REDEFINITION.ABORT_REDEF_TABLE ('test1','t_objects','t_objects_temp');

PL/SQL procedure successfully completed.

SQL> select * from cat;

TABLE_NAME TABLE_TYPE

------------------------------ -----------

T_OBJECTS TABLE

T_OBJECTS_TEMP TABLE

Oracle 基于 dbms_redefinition 在线重定义表