使用克隆现存PDB的方式创建新的PDB：这里有两种情况，一种为使用本地PDB，另外一种为使用远程PDB。二者并无太大差异。只是第二种需要使用DBLINK而已。
克隆本地方式：
SYS@ora12g> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ WRITE YES 4 ORACDB_PDB2 READ WRITE NO SYS@ora12g> alter pluggable database ORA12C_PDB1 close; Pluggable database altered. SYS@ora12g> alter pluggable database ORA12C_PDB1 open read only; Pluggable database altered. SYS@ora12g> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ ONLY NO 4 ORACDB_PDB2 READ WRITE NO
--我们这里克隆ORA12C_PDB1来创建新的PDB，需要先将其置于read only模式。
SYS@ora12c> alter session set container=ORA12C_PDB1; Session altered. SYS@ora12c> select file_name from dba_data_files; FILE_NAME -------------------------------------------------------------------------------- /u01/oracle/oradata/ora12c/ora12c_pdb1/system01.dbf /u01/oracle/oradata/ora12c/ora12c_pdb1/sysaux01.dbf /u01/oracle/oradata/ora12c/ora12c_pdb1/SAMPLE_SCHEMA_users01.dbf /u01/oracle/oradata/ora12c/ora12c_pdb1/example01.dbf SYS@ora12c> create pluggable database ORA12C_PDB2 from ORA12c_PDB1 file_name_convert = ('/u01/oracle/oradata/ora12c/ora12c_pdb1', '/u01/oracle/oradata/ora12c/ora12c_pdb2') storage (MAXSIZE 4G MAX_SHARED_TEMP_SIZE 100M); 2 3 4 5 create pluggable database ORA12C_PDB2 * ERROR at line 1: ORA-65040: operation not allowed from within a pluggable database
--不能在PDB中复制PDB。
SYS@ora12c> alter session set container=CDB$ROOT; Session altered. SYS@ora12c> create pluggable database ORA12C_PDB2 from ORA12C_PDB1 file_name_convert = ('/u01/oracle/oradata/ora12c/ora12c_pdb1', '/u01/oracle/oradata/ora12c/ora12c_pdb2') storage (MAXSIZE 4G MAX_SHARED_TEMP_SIZE 100M); 2 3 4 5 Pluggable database created.
--目标PDB的数据文件存储目录也可以不用事先创建，oracle会自动创建。
--可以在创建PDB的同时指定该PDB的空间使用限额。
SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ ONLY NO 4 ORACDB_PDB2 READ WRITE NO 5 ORA12C_PDB2 MOUNTED
使用远程PDB创建：
SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ ONLY NO 4 ORACDB_PDB2 READ WRITE NO 5 ORA12C_PDB2 MOUNTED SYS@ora12c> conn sys/oracle@ORACDB_PDB2 as sysdba Connected. SYS@ORACDB_PDB2> shutdown immediate; Pluggable Database closed. SYS@ORACDB_PDB2> startup; Pluggable Database opened. SYS@ORACDB_PDB2> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 4 ORACDB_PDB2 READ WRITE NO SYS@ORACDB_PDB2> create user remote_pdb identified by remote; User created. SYS@ORACDB_PDB2> grant create pluggable database to remote_pdb; Grant succeeded.
--在源PDB中创建拥有create PDB权限的用户。
SYS@ORACDB_PDB2> conn / as sysdba Connected. SYS@ora12g> create database link dbl_pdb connect to remote_pdb identified by remote using 'ORACDB_PDB2'; Database link created.
--我们这里以ORACDB_PDB2作为远程数据库，也就是创建PDB的源PDB。
--利用前面创建的用户创建db link。
SYS@ora12c> alter pluggable database ORACDB_PDB2 open read only force; Pluggable database altered. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ ONLY NO 4 ORACDB_PDB2 READ ONLY NO 5 ORA12C_PDB2 MOUNTED
--同样将其置于read only状态。
SYS@ora12c> create pluggable database ORACDB_PDB_NEW from ORACDB_PDB2@dbl_pdb file_name_convert = ('/u01/oracle/oradata/ora12c/cdb/pdb2', '/u01/oracle/oradata/ora12c/cdb/pdb2_new'); 2 3 4 Pluggable database created. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12G_PDB1 READ ONLY NO 4 ORACDB_PDB2 READ ONLY NO 5 ORA12C_PDB2 MOUNTED 6 ORACDB_PDB_NEW MOUNTED
克隆非CDB的数据库来创建PDB。
这里有三种方法：
1，使用DBMS_PDB包生成源数据库的元数据，然后再利用create pluggable database语句创建；
2，使用数据泵（可传输表空间）；
3，使用OGG。
使用数据泵方式，请参考官方文档Oracle® Database Utilities 12c Release 1 (12.1)
使用OGG方式，请参阅OGG相关文档。
我们这里测试下第一种方式。
1，先创建一个新的非CDB数据库。我们这里用DBCA创建。这步我就不多写了。各位一路next下去就好。记得别勾选create as a container database即可。
另外需要注意的是，数据库版本必须得是12c或者更高版本。
2，将该数据库以read only模式打开
[oracle@ora12 ~]$ sqlplus / as sysdba SQL*Plus: Release 12.1.0.2.0 Production on Fri Dec 18 09:56:43 2015 Copyright (c) 1982, 2014, Oracle. All rights reserved. Connected to: Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options SYS@noncdb> shutdown immediate; Database closed. Database dismounted. ORACLE instance shut down. SYS@noncdb> startup mount; ORACLE instance started. Total System Global Area 838860800 bytes Fixed Size 2929936 bytes Variable Size 599788272 bytes Database Buffers 230686720 bytes Redo Buffers 5455872 bytes Database mounted. SYS@noncdb> alter database open read only; Database altered.
--这里，数据库需要开归档才能以read only模式打开，至于原因嘛，恩，各位小伙伴应该都能想的出来吧
3，利用DBMS_PDB包生成该数据库的pdb描述文件并关闭数据库。
SYS@noncdb> begin dbms_pdb.describe(pdb_descr_file => '/home/oracle/noncdb.xml'); end; / PL/SQL procedure successfully completed. SYS@noncdb> SYS@noncdb> shutdown immediate; Database closed. Database dismounted. ORACLE instance shut down.
--这里生成的pdb描述文件为xml格式的，各位可以进去看一下它的内容。
--该文件中包含了数据库的版本信息，非默认值的初始化参数信息，表空间及数据文件信息，其他可选组件的版本信息，service信息，以及AWR中loadprofile的内容。
4，登陆CDB，检测要插入的pdb是否存在兼容性问题
SYS@ora12c> set serveroutput on declare test_via boolean; begin test_via := dbms_pdb.check_plug_compatibility(pdb_descr_file => '/home/oracle/noncdb.xml'); if test_via then dbms_output.put_line('Yes'); else dbms_output.put_line('No'); end if; end; / Yes PL/SQL procedure successfully completed.
--输出结果为yes，表示没有兼容性问题。
--如果为no，则需要去检查pdb_plug_in_violations视图。
5，创建PDB
SYS@ora12c> create pluggable database PDB_NEW using '/home/oracle/noncdb.xml' copy file_name_convert = ('/u01/oracle/oradata/noncdb', '/u01/oracle/oradata/cdb/pdb_new'); Pluggable database created. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 PDB_NEW MOUNTED
6，执行脚本
SYS@ora12c> conn sys/oracle@ora12:1521/PDB_NEW as sysdba; Connected. SYS@ora12:1521/PDB_NEW> @?/rdbms/admin/noncdb_to_pdb.sql;
--该脚本的用处是：更新非CDB的数据库中的数据字典表，将其调整为PDB。
执行完成之后，该PDB就可以使用了。
需要注意的是：
在执行该脚本的时候，建议同时查看alert 日志，因为我的虚拟机只有2G内存，然后新创建的这个数据库noncdb我将其内存设置为了800M。所以在将该数据库创建为PDB时，oracle需要调整其参数设置。alert 日志中就看到如下类似的内容：
Active Session History (ASH) performed an emergency flush. This may mean that ASH is undersized. If emergency flushes are a recurring issue, you may consider increasing ASH size by setting the value of _ASH_SIZE to a sufficiently large value. Currently, ASH size is 2097152 bytes. Both ASH size and the total number of emergency flushes since instance startup can be monitored by running the following query: select total_size,awr_flush_emergency_count from v$ash_info;
以及：
Default pga_aggregate_limit value is too high for the amount of physical memory in the system pga_aggregate_limit is 2048 MB limit based on physical memory and SGA usage is 1285 MB
因此，在虚拟机上创建新的PDB时，需要考虑内存以及其他比如说磁盘容量等方面的限制。
从CDB中拔出和插入PDB：
SYS@ora12c> create pluggable database PDB1 2 admin user test_admin identified by test 3 file_name_convert = ('/u01/oracle/oradata/ora12c/pdbseed','/u01/oracle/oradata/ora12c/cdb/pdb1'); Pluggable database created. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 PDB1 MOUNTED SYS@ora12c> alter pluggable database PDB1 open; Pluggable database altered. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 PDB1 READ WRITE NO SYS@ora12c> alter pluggable database PDB1 close; Pluggable database altered.
--需要先关闭可插拔数据库，然后再unplug。
SYS@ora12c> alter pluggable database PDB1 unplug into '/home/oracle/pdb1.xml'; Pluggable database altered.
--需要注意的是，这里只是unplug了，实际上该PDB还存在。如果想重新插入该PDB，则需要先删除。
SYS@ora12c> drop pluggable database PDB1; Pluggable database dropped.
插入PDB的时候，首先需要做兼容性检查。也就是上篇文章中提到的DBMS_PDB.check_plug_compatibility函数。
如果没有问题，再插入。
插入语句跟创建新的PDB一样
SYS@ora12c> create pluggable database PDB1 using '/home/oracle/pdb1.xml' copy file_name_convert = ('/u01/oracle/oradata/pdb1', '/u01/oracle/oradata/cdb/pdb_new');
使用DBCA创建PDB的方式，这里不再多说
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