使用DB2 RESTORE 克隆数据库
使用DB2 RESTORE 克隆数据库
开发team需要克隆一个数据库，只更改库名，但是库里面的信息如表空间，表等对象不做变化。经指导可以使用RESTORE REDIRECT进行数据库克隆。
重定向恢复操作核心步骤有三步，包括两步数据库恢复过程，一个表空间容器重定义：
1）带 REDIRECT 选项发出 RESTORE DATABASE 命令。
2）使用 SET TABLESPACE CONTAINERS 命令来定义被恢复的数据库的表空间容器（克隆库的存放位置有关）。
3）再次发出 RESTORE DATABASE 命令，这次指定 CONTINUE 选项。
需要注意的是整个重定向恢复操作要在同一个session中，否则恢复操作会失败。
具体步骤如下：
1. 备份数据库
db2 backup db testdb online
2. 使用RESTORE重定向进行克隆
db2 restore db testdb taken at 20151202102547 dbpath on /disk2/testdbz/ into testdbz redirect
SQL1277W A redirected restore operation is being performed. During a table
space restore, only table spaces being restored can have their paths
reconfigured. During a database restore, storage group storage paths and DMS
table space containers can be reconfigured.
DB20000I The RESTORE DATABASE command completed successfully.
3. 在另一个session中查看testdb表空间容器信息
查看原库表空间容器：
0x00007F252DEF9120 0 0 File 131072 131040 - 0 /disk1/testdb/syscatspace_c1
0x00007F252DEF9780 1 0 Path 1 1 - 0 /disk1/testdb/tempspace1
0x00007F252DEDAC60 2 0 File 262144 262112 - 0 /disk1/testdb/userspace_c1
0x00007F252DED69E0 3 0 File 2621440 2621408 - 0 /disk1/testdb/cas_data8k_c1
0x00007F252DED2B80 4 0 File 4096 4092 - 0 /disk1/testdb/db2inst1/NODE0000/SQL00001/SYSTOOLSPACE
0x00007F252DED17A0 5 0 File 2621440 2621408 - 0 /disk1/testdb/cas_idx8k_c1
4. 重定向克隆库容器：
db2 "set tablespace containers for 0 using ( file '/disk2/testdbz/syscatspace_c1' 131072)"
db2 "set tablespace containers for 1 using ( path '/disk2/testdbz/tempspace1')"
db2 "set tablespace containers for 2 using ( file '/disk2/testdbz/userspace_c1' 262144)"
db2 "set tablespace containers for 3 using ( file '/disk2/testdbz/cas_data8k_c1' 2621440)"
db2 "set tablespace containers for 4 using ( file '/disk2/testdbz/db2inst1/NODE0000/SQL00001/SYSTOOLSPACE' 4096)"
db2 "set tablespace containers for 5 using ( file '/disk2/testdbz/cas_idx8k_c1' 2621440)"
5. 继续restore：
db2 restore db testdb continue
6. 前滚：
db2 "rollforward db testdbz to end of logs and complete"
此处可能会报错：log missing
SQL1273N An operation reading the logs on database "testdbZ" cannot continue
because of a missing log file "S0000000.LOG" on database partition "0" and log
stream "0".
从原库中将missing的log拷贝到克隆库的日志存放目录即可。
ls
S0000000.LOG S0000002.LOG S0000004.LOG S0000006.LOG S0000008.LOG S0000010.LOG S0000012.LOG
S0000001.LOG S0000003.LOG S0000005.LOG S0000007.LOG S0000009.LOG S0000011.LOG S0000013.LOG
cp S0000000.LOG /disk2/testdbz/db2inst1/NODE0000/SQL00001/LOGSTREAM0000/
7. 继续前滚
db2 "rollforward db testdbz to end of logs and complete"
Rollforward Status
Input database alias = testdbz
Number of members have returned status = 1
Member ID = 0
Rollforward status = not pending
Next log file to be read =
Log files processed = S0000000.LOG - S0000000.LOG
Last committed transaction = 2015-12-02-02.25.49.000000 UTC
DB20000I The ROLLFORWARD command completed successfully.
至此testdb的克隆库testdbz就建好了。