EXPDP/IMPDP与EXP/IMP在不同用户和表空间之间迁移数据的实现方法

1. EXPDP/IMPDP方式


SQL> create user zlm identified by zlm;


User created.


SQL> grant connect,resource to zlm;


Grant succeeded.


SQL> create tablespace ts_zlm datafile '/u01/app/oracle/oradata/ora10g/zlm01.dbf' size 100M reuse;


Tablespace created.


SQL> alter user zlm default tablespace ts_zlm;


User altered.


SQL> select username,default_tablespace from dba_users where username='ZLM';


USERNAME                       DEFAULT_TABLESPACE
------------------------------ ------------------------------
ZLM                            TS_ZLM


SQL> col name for a50
SQL> select name,bytes/1024/1024 from v$datafile where name like '%users01.dbf';


NAME                                               BYTES/1024/1024
-------------------------------------------------- ---------------
/u01/app/oracle/oradata/ora10g/users01.dbf                       5


SQL> set lin 120 pages 120
SQL> col username for a8
SQL> col name for a45
SQL> select a.username,a.default_tablespace,b.name from dba_users a,v$datafile b,v$tablespace c where a.default_tablespace=c.name and b.ts#=c.ts# and a.username='SCOTT'; 


USERNAME DEFAULT_TABLESPACE             NAME
-------- ------------------------------ ---------------------------------------------
SCOTT    USERS                          /u01/app/oracle/oradata/ora10g/users01.dbf


SQL> alter database datafile '/u01/app/oracle/oradata/ora10g/users01.dbf' resize 100M;


Database altered.


SQL> select name,bytes/1024/1024 from v$datafile where name like '%users01.dbf';


NAME                                          BYTES/1024/1024
--------------------------------------------- ---------------
/u01/app/oracle/oradata/ora10g/users01.dbf                100




SQL> select owner,directory_name from dba_directories;




OWNER                          DIRECTORY_NAME
------------------------------ ------------------------------
SYS                            DATA_PUMP_DIR
SYS                            SUBDIR
SYS                            XMLDIR
SYS                            MEDIA_DIR
SYS                            LOG_FILE_DIR
SYS                            DATA_FILE_DIR
SYS                            WORK_DIR
SYS                            ADMIN_DIR


SQL> create directory zlm_pump as '/u01/expdp';


Directory created.


SQL> !mkdir /u01/expdp


SQL> alter user scott identified by tiger account unlock;


User altered.


SQL> grant connect,resource to scott;


Grant succeeded.


SQL> grant read,write on directory zlm_pump to scott;


Grant succeeded.


SQL> conn scott/tiger
Connected.
SQL> create table zlm1 as select * from dba_objects;


Table created.


SQL> insert into zlm1 select * from dba_objects;


50318 rows created.


SQL> /


50318 rows created.


SQL> select count(*) from zlm1;


  COUNT(*)
----------
    150954


SQL> select table_name from user_tables where tablespace_name='USERS';


TABLE_NAME
------------------------------
ZLM1
SALGRADE
BONUS
EMP
DEPT


[oracle@ora10g ~]$ expdp scott/tiger parallel=2 directory=zlm_pump dumpfile=scott01.dmp,scott02.dmp tablespaces=users


Export: Release 10.2.0.1.0 - Production on Sunday, 31 August, 2014 14:35:29


Copyright (c) 2003, 2005, Oracle.  All rights reserved.


Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
Starting "SCOTT"."SYS_EXPORT_TABLESPACE_01":  scott/******** parallel=2 directory=zlm_pump dumpfile=scott01.dmp,scott02.dmp tablespaces=users 
Estimate in progress using BLOCKS method...--可以通过estimate=block(默认值)指定，还有一个是statistic
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 17.18 MB
Processing object type TABLE_EXPORT/TABLE/TABLE
. . exported "SCOTT"."ZLM1"                              14.06 MB  150954 rows
. . exported "SCOTT"."DEPT"                              5.656 KB       4 rows
. . exported "SCOTT"."EMP"                               7.820 KB      14 rows
. . exported "SCOTT"."SALGRADE"                          5.585 KB       5 rows
. . exported "SCOTT"."BONUS"                                 0 KB       0 rows
Processing object type TABLE_EXPORT/TABLE/INDEX/INDEX
Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type TABLE_EXPORT/TABLE/COMMENT
Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/REF_CONSTRAINT
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Master table "SCOTT"."SYS_EXPORT_TABLESPACE_01" successfully loaded/unloaded
******************************************************************************
Dump file set for SCOTT.SYS_EXPORT_TABLESPACE_01 is:
  /u01/expdp/scott01.dmp
  /u01/expdp/scott02.dmp
Job "SCOTT"."SYS_EXPORT_TABLESPACE_01" successfully completed at 14:36:10


[oracle@ora10g ~]$ impdp zlm/zlm parallel=2 remap_schema=scott:zlm remap_tablespace=users:ts_zlm directory=zlm_pump dumpfile=scott01.dmp,scott02.dmp
 
Import: Release 10.2.0.1.0 - Production on Sunday, 31 August, 2014 14:41:30


Copyright (c) 2003, 2005, Oracle.  All rights reserved.


Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
Master table "ZLM"."SYS_IMPORT_FULL_01" successfully loaded/unloaded
Starting "ZLM"."SYS_IMPORT_FULL_01":  zlm/******** parallel=2 remap_schema=scott:zlm remap_tablespace=users:ts_zlm directory=zlm_pump dumpfile=scott01.dmp,scott02.dmp 
Processing object type TABLE_EXPORT/TABLE/TABLE
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
. . imported "ZLM"."DEPT"                                5.656 KB       4 rows
. . imported "ZLM"."EMP"                                 7.820 KB      14 rows
. . imported "ZLM"."SALGRADE"                            5.585 KB       5 rows
. . imported "ZLM"."BONUS"                                   0 KB       0 rows
. . imported "ZLM"."ZLM1"                                14.06 MB  150954 rows
Processing object type TABLE_EXPORT/TABLE/INDEX/INDEX
Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/REF_CONSTRAINT
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Job "ZLM"."SYS_IMPORT_FULL_01" successfully completed at 14:41:43
[oracle@ora10g ~]$ sqlplus /nolog


SQL*Plus: Release 10.2.0.1.0 - Production on Sun Aug 31 14:43:12 2014


Copyright (c) 1982, 2005, Oracle.  All rights reserved.


SQL> conn zlm/zlm
Connected.
SQL> select table_name from user_tables where tablespace_name='TS_ZLM';


TABLE_NAME
------------------------------
ZLM1
SALGRADE
BONUS
EMP
DEPT


SQL> select object_name from user_objects;


OBJECT_NAME
--------------------------------------------------------------------------------
DEPT
EMP
BONUS
SALGRADE
ZLM1
PK_DEPT
PK_EMP


SCHEMA SCOTT的表空间USERS中的全部对象已经被导入到SCHEMA ZLM的表空间，包括表和索引


2. EXP/IMP方式


SQL> conn / as sysdba
Connected.
SQL> drop user zlm cascade;


User dropped.


SQL> create user zlm identified by zlm;


User created.


SQL> grant connect,resource to zlm;


Grant succeeded.


SQL> alter user zlm default tablespace ts_zlm;


User altered.


SQL> conn zlm/zlm
Connected.
SQL> select * from cat;


no rows selected


SQL> !
[oracle@ora10g ~]$ exp scott/tiger owner=scott file=/u01/scott01.dmp                                                       


Export: Release 10.2.0.1.0 - Production on Sun Aug 31 15:42:00 2014


Copyright (c) 1982, 2005, Oracle.  All rights reserved.




Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
Export done in US7ASCII character set and AL16UTF16 NCHAR character set
server uses ZHS16GBK character set (possible charset conversion)
. exporting pre-schema procedural objects and actions
. exporting foreign function library names for user SCOTT 
. exporting PUBLIC type synonyms
. exporting private type synonyms
. exporting object type definitions for user SCOTT 
About to export SCOTT's objects ...
. exporting database links
. exporting sequence numbers
. exporting cluster definitions
. about to export SCOTT's tables via Conventional Path ...
. . exporting table                          BONUS          0 rows exported
EXP-00091: Exporting questionable statistics.
. . exporting table                           DEPT          4 rows exported
EXP-00091: Exporting questionable statistics.
EXP-00091: Exporting questionable statistics.
. . exporting table                            EMP         14 rows exported
EXP-00091: Exporting questionable statistics.
EXP-00091: Exporting questionable statistics.
. . exporting table                       SALGRADE          5 rows exported
EXP-00091: Exporting questionable statistics.
. . exporting table                           ZLM1     150954 rows exported
. exporting synonyms
. exporting views
. exporting stored procedures
. exporting operators
. exporting referential integrity constraints
. exporting triggers
. exporting indextypes
. exporting bitmap, functional and extensible indexes
. exporting posttables actions
. exporting materialized views
. exporting snapshot logs
. exporting job queues
. exporting refresh groups and children
. exporting dimensions
. exporting post-schema procedural objects and actions
. exporting statistics
Export terminated successfully with warnings.
[oracle@ora10g ~]$ imp zlm/zlm fromuser=scott touser=zlm file=/u01/exp/scott01.dmp


Import: Release 10.2.0.1.0 - Production on Sun Aug 31 15:43:01 2014


Copyright (c) 1982, 2005, Oracle.  All rights reserved.




Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options


IMP-00002: failed to open /u01/exp/scott01.dmp for read   --路径指定错了
Import file: expdat.dmp > /u01/scott01.dmp


Export file created by EXPORT:V10.02.01 via conventional path


Warning: the objects were exported by SCOTT, not by you


import done in US7ASCII character set and AL16UTF16 NCHAR character set
import server uses ZHS16GBK character set (possible charset conversion)
. . importing table                        "BONUS"          0 rows imported
. . importing table                         "DEPT"          4 rows imported
. . importing table                          "EMP"         14 rows imported
. . importing table                     "SALGRADE"          5 rows imported
. . importing table                         "ZLM1"     150954 rows imported
About to enable constraints...
Import terminated successfully with warnings.
[oracle@ora10g ~]$ exit
SQL> col object_name for a15
SQL> select object_name,object_type from user_objects;


OBJECT_NAME     OBJECT_TYPE
--------------- -------------------
BONUS           TABLE
DEPT            TABLE
PK_DEPT         INDEX
EMP             TABLE
PK_EMP          INDEX
SALGRADE        TABLE
ZLM1            TABLE


SQL> select table_name,tablespace_name from user_tables;


TABLE_NAME                     TABLESPACE_NAME
------------------------------ ------------------------------
BONUS                          USERS
DEPT                           USERS
EMP                            USERS
SALGRADE                       USERS
ZLM1                           USERS

注意，用imp导入后的对象，都是存放在exp导出时的表空间的，如果要迁移到别的表空间，就要 使用alter table move tablespace来实现， 先通过下面的SQL拼接语句来获得批量move的语句：

SQL> select 'alter table '||table_name||' MOVE TABLESPACE ts_zlm;' from user_tables; 


'ALTERTABLE'||TABLE_NAME||'MOVETABLESPACETS_ZLM;'
------------------------------------------------------------------
alter table BONUS MOVE TABLESPACE ts_zlm;
alter table DEPT MOVE TABLESPACE ts_zlm;
alter table EMP MOVE TABLESPACE ts_zlm;
alter table SALGRADE MOVE TABLESPACE ts_zlm;
alter table ZLM1 MOVE TABLESPACE ts_zlm;


SQL> select 'ALTER INDEX ' ||index_name || ' REBUILD TABLESPACE ts_zlm;' from user_indexes;


'ALTERINDEX'||INDEX_NAME||'REBUILDTABLESPACETS_ZLM;'
---------------------------------------------------------------------
ALTER INDEX PK_EMP REBUILD TABLESPACE ts_zlm;
ALTER INDEX PK_DEPT REBUILD TABLESPACE ts_zlm;


SQL> select table_name,tablespace_name from user_tables;


TABLE_NAME                     TABLESPACE_NAME
------------------------------ ------------------------------
SALGRADE                       TS_ZLM
EMP                            TS_ZLM
ZLM1                           TS_ZLM
DEPT                           TS_ZLM
BONUS                          TS_ZLM


SQL> select index_name,tablespace_name from user_indexes;


INDEX_NAME                     TABLESPACE_NAME
------------------------------ ------------------------------
PK_EMP                         TS_ZLM
PK_DEPT                        TS_ZLM

可以看到，zlm用户imp导入的数据库对象已经全部迁移到TS_ZLM表空间去了

总结：

EXPDP/IPMDP只能在server上运行，其运行效率完全取决于磁盘I/O，而EXP/IMP不仅可以运行在server上，也可以运行在client上，所以除了磁盘I/O的制约因素，还有网络方面的因素。

EXPDP/IMPDP比EXP/IMP性能有很大的提高，其中影响最大的就是paralle，通常设置为CPU的个数，通过该参数可以并行导出，大大提高导出速度，而EXP/IMP是没有这个功能的，最多也就只有一个DIRECT=Y,使导出不用经过SELECT到SGA的BUFFER中，提高的速度是有限的，注意他们之间的语法也有不小的区别，参数不可互相替代。

EXPDP/IMPDP可以通过remap_schema和remap_tablespace直接实现不同用户和表空间之间的数据迁移;而EXP/IMP则稍微麻烦一点，需要ALTER TABLE xxx MOVE TABLESPACE xxx/ALTER INDEX xxx REBUILD TABLESPACE xxx方式来实现。move相当于把表再重建一次，可以修改storage参数(如initial、pctfree、pctincrease等)，还可以move到另外的表空间，如果不指定表空间，则在原来的表空间中move，因此做move操作时，目标表空间需要保证有这个表同样大小的剩余空间，整个操作相当于exp/imp(从表空间A导出到表空间B)，move完表后要重建索引。

基于以上几种原因，现在做数据逻辑迁移都是用EXPDP/IMPDP而很少再使用EXP/IMP了。