代码驿站移动版

当前位置：主页 > 数据库 > Oracle >

Oracle数据库备份还原详解

时间：2022-04-27 10:27:09 | 栏目：Oracle | 点击：次

理论准备

oracle 数据库提供expdp和impdp命令用于备份和恢复数据库。

具体可查阅oracle官方文档 https://docs.oracle.com/en/database/oracle/oracle-database/12.2/sutil/database-utilities.pdf

备份和还原主要有

FULL_MODE:整个数据库进行备份还原。

Schema Mode：默认导出模式，Schema 模式。

Table Mode：表模式。

Tablespace Mode：表空间模式。

实践

验证1：备份某一时刻数据库数据，通过恢复语句能够恢复到备份时刻的数据。

切换用户后登录

[root@linuxtestb538 ~]# su oracle
bash-4.2$ sqlplus / as sysdba

SQL*Plus: Release 19.0.0.0.0 - Production on Tue Nov 23 14:40:45 2021
Version 19.3.0.0.0

Copyright (c) 1982, 2019, Oracle.  All rights reserved.


Connected to:
Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Version 19.3.0.0.0

SQL>

连接到对应用户下

SQL> conn test/test@mypdb
Connected.

创建了test_tab表

create table test_tab(
id number(9) not null,
title varchar2(20)
);

插入一条数据

insert into test_tab values(1,'hello world');

导出数据文件(推出数据库连接)

expdp test/test@mypdb schemas=test dumpfile=test20211119_all.dmp logfile=20211119_all.dmp DIRECTORY=DATA_PUMP_DIR

插入一条数据

insert into test_tab values(2,'hello test');

目前数据库中存在两条数据,而数据导出的时候只有一条hello world的数据。

SQL> select * from test_tab;

        ID TITLE
---------- --------------------
         1 hello world
         2 hello test

现在我们通过impdp命令恢复数据库数据

bash-4.2$ impdp test/test@mypdb schemas=test DIRECTORY=DATA_PUMP_DIR DUMPFILE=test20211119_all.dmp logfile=20211119_recov.dmp;

Import: Release 19.0.0.0.0 - Production on Tue Nov 23 14:52:21 2021
Version 19.3.0.0.0

Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.

Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Master table "TEST"."SYS_IMPORT_SCHEMA_01" successfully loaded/unloaded
Starting "TEST"."SYS_IMPORT_SCHEMA_01":  test/********@mypdb schemas=test DIRECTORY=DATA_PUMP_DIR DUMPFILE=test20211119_all.dmp logfile=20211119_recov.dmp 
Processing object type SCHEMA_EXPORT/USER
ORA-31684: Object type USER:"TEST" already exists

Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT
Processing object type SCHEMA_EXPORT/DEFAULT_ROLE
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/TABLE/TABLE
ORA-39151: Table "TEST"."TEST_TAB" exists. All dependent metadata and data will be skipped due to table_exists_action of skip

Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type SCHEMA_EXPORT/STATISTICS/MARKER
Job "TEST"."SYS_IMPORT_SCHEMA_01" completed with 2 error(s) at Tue Nov 23 14:52:37 2021 elapsed 0 00:00:14

从输入信息中看到test_tab表已经存在所以相关的备份数据跳过不处理，但我们的本意需要让备份数据去覆盖现有数据不管现在表 是否已经存在。那我们需要增加 table_exists_action=replace的参数

impdp test/test@mypdb schemas=test table_exists_action=replace DIRECTORY=DATA_PUMP_DIR DUMPFILE=test20211119_all.dmp logfile=20211119_recov.dmp;

Import: Release 19.0.0.0.0 - Production on Tue Nov 23 14:55:57 2021
Version 19.3.0.0.0

Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.

Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Master table "TEST"."SYS_IMPORT_SCHEMA_01" successfully loaded/unloaded
Starting "TEST"."SYS_IMPORT_SCHEMA_01":  test/********@mypdb schemas=test table_exists_action=replace DIRECTORY=DATA_PUMP_DIR DUMPFILE=test20211119_all.dmp logfile=20211119_recov.dmp 
Processing object type SCHEMA_EXPORT/USER
ORA-31684: Object type USER:"TEST" already exists

Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT
Processing object type SCHEMA_EXPORT/DEFAULT_ROLE
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/TABLE/TABLE
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
. . imported "TEST"."TEST_TAB"                           5.539 KB       1 rows
Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type SCHEMA_EXPORT/STATISTICS/MARKER
Job "TEST"."SYS_IMPORT_SCHEMA_01" completed with 1 error(s) at Tue Nov 23 14:56:25 2021 elapsed 0 00:00:27

连接到数据库后,查询test_tab表，发现数据已经恢复到只有一条hello world的时候，验证通过。

SQL> select * from test_tab;

        ID TITLE
---------- --------------------
         1 hello world

验证2：备份数据的时候不想备份所有表，要根据条件过滤掉某些表进行备份，恢复的时候只恢复备份出来的表数据。

我们再创建一张his开头的表

create table his_test_tab(
id number(9) not null,
title varchar2(20)
);

插入数据

insert into his_test_tab values(1,'hello world');

导出数据

bash-4.2$ expdp test/test@mypdb schemas=test dumpfile=test20211123-1_all.dmp logfile=20211123-1_all.dmp DIRECTORY=DATA_PUMP_DIR EXCLUDE=table:\"like \'HIS%\'\";

Export: Release 19.0.0.0.0 - Production on Tue Nov 23 15:16:39 2021
Version 19.3.0.0.0

Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.

Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Starting "TEST"."SYS_EXPORT_SCHEMA_01":  test/********@mypdb schemas=test dumpfile=test20211123-1_all.dmp logfile=20211123-1_all.dmp DIRECTORY=DATA_PUMP_DIR EXCLUDE=table:"like 'HIS%'" 
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type SCHEMA_EXPORT/STATISTICS/MARKER
Processing object type SCHEMA_EXPORT/USER
Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT
Processing object type SCHEMA_EXPORT/DEFAULT_ROLE
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/TABLE/TABLE
Processing object type SCHEMA_EXPORT/TABLE/COMMENT
Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX
. . exported "TEST"."TEST_TAB"                           5.539 KB       1 rows
Master table "TEST"."SYS_EXPORT_SCHEMA_01" successfully loaded/unloaded
******************************************************************************
Dump file set for TEST.SYS_EXPORT_SCHEMA_01 is:
  /opt/oracle/admin/ORCLCDB/dpdump/D0F96921D5E99512E0534390140A837F/test20211123-1_all.dmp
Job "TEST"."SYS_EXPORT_SCHEMA_01" successfully completed at Tue Nov 23 15:17:39 2021 elapsed 0 00:01:00

在test_tab和his_test_tab 表中新增数据

SQL> insert into test_tab values(2,'hello test');

1 row created.

SQL> insert into his_tab values(2,'hello test');
insert into his_tab values(2,'hello test')
            *
ERROR at line 1:
ORA-00942: table or view does not exist


SQL> select * from test_tab;

        ID TITLE
---------- --------------------
         1 hello world
         2 hello test

SQL> select * from his_test_tab;

        ID TITLE
---------- --------------------
         1 hello world
         2 hello test

插入数据后test_tab和his_test_tab表中

还原数据

bash-4.2$ impdp test/test@mypdb schemas=test table_exists_action=replace DIRECTORY=DATA_PUMP_DIR DUMPFILE=test20211123-1_all.dmp logfile=20211123_recov.dmp;

Import: Release 19.0.0.0.0 - Production on Tue Nov 23 15:24:37 2021
Version 19.3.0.0.0

Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.

Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Master table "TEST"."SYS_IMPORT_SCHEMA_01" successfully loaded/unloaded
Starting "TEST"."SYS_IMPORT_SCHEMA_01":  test/********@mypdb schemas=test table_exists_action=replace DIRECTORY=DATA_PUMP_DIR DUMPFILE=test20211123-1_all.dmp logfile=20211123_recov.dmp 
Processing object type SCHEMA_EXPORT/USER
ORA-31684: Object type USER:"TEST" already exists

Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT
Processing object type SCHEMA_EXPORT/DEFAULT_ROLE
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/TABLE/TABLE
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
. . imported "TEST"."TEST_TAB"                           5.539 KB       1 rows
Processing object type SCHEMA_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type SCHEMA_EXPORT/STATISTICS/MARKER
Job "TEST"."SYS_IMPORT_SCHEMA_01" completed with 1 error(s) at Tue Nov 23 15:24:47 2021 elapsed 0 00:00:09

确认结果

SQL> select * from his_test_tab;

        ID TITLE
---------- --------------------
         1 hello world
         2 hello test

SQL> select * from test_tab;

        ID TITLE
---------- --------------------
         1 hello world

结果符合预期test_tab数据被还原，his_test_tab数据没有被还原。通过备份日志也可以看到我们只备份了test_tab表中的数据。

您可能感兴趣的文章:

相关文章