我们先切换回根容器：
SYS@ora12c> alter session set container=CDB$ROOT; Session altered.
接下来我们来创建用户及角色：
在12c中，如果我们还是按照11g以及以前版本中的命令来创建用户和角色，那是要报错的。因为12c中新引入了common_user_prefix参数，也就是说，你创建用户或者角色时，需要指定名称前缀，默认为c##。对于os认证的用户，也有相关的约束，参数为os_authent_prefix。
我们可以将该参数做一下处理。
SYS@ora12c> alter system set common_user_prefix='' scope=spfile; System altered. SYS@ora12c> startup force; ORACLE instance started. Total System Global Area 838860800 bytes Fixed Size 2929936 bytes Variable Size 687868656 bytes Database Buffers 142606336 bytes Redo Buffers 5455872 bytes Database mounted. Database opened. SYS@ora12c> show parameter common_user_prefix; NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ common_user_prefix string SYS@ora12c> create user test_u1 identified by test container=current; create user test_u1 identified by test container=current * ERROR at line 1: ORA-65049: creation of local user or role is not allowed in CDB$ROOT
--在根容器中，不能创建本地用户。
SYS@ora12c> create user test_u1 identified by test container=all; User created.
切换到种子容器试试：
SYS@ora12c> alter session set container=PDB$SEED; Session altered. SYS@ora12c> create user test_u3 identified by test container=current; create user test_u3 identified by test container=current * ERROR at line 1: ORA-00604: error occurred at recursive SQL level 1 ORA-16000: database or pluggable database open for read-only access SYS@ora12c> alter session set container=ora12c_pdb1; Session altered. SYS@ora12c> create user test_u3 identified by test container=current; create user test_u3 identified by test container=current * ERROR at line 1: ORA-01109: database not open SYS@ora12c> startup; Pluggable Database opened. SYS@ora12c> create user test_u3 identified by test container=current; User created. SYS@ora12c> create user test_u3 identified by test container=all; create user test_u3 identified by test container=all * ERROR at line 1: ORA-65050: Common DDLs only allowed in CDB$ROOT
也就是说，在根容器中创建用户，container默认为all；在某一可插拔数据库中创建用户，container默认为current；种子容器中不允许创建用户。
角色也是如此。
CDB的管理操作，我们不再多说，想了解更多细节的话，可以查阅官方文档管理员手册的第40、41两章。
接下来，我们来看看PDB的创建与管理。
oracle提供了多种创建或者克隆PDB的工具，比如说create pluggable database语句，比如说DBCA，再比如说EMCC（Enterprise Manager Cloud Control）。关于如何使用EMCC图形化的方式创建PDB，可以参考管理员手册的第39章。我们这里着重关注如何使用命令行来创建或者复制PDB。
通过create pluggable database语句，可以使用如下资源创建PDB:
1，种子容器；
2，已经存在的PDB（本地和远程的均可）；
3，非CDB数据库；
4，被拔出的PDB。
如果使用DBCA，则可以使用如下资源创建PDB:
1，种子容器；
2，RMAN备份；
3，已被拔出的PDB。
先看如何使用create pluggable database语句来创建PDB：
使用克隆种子容器的方式：
SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 3 ORA12C_PDB1 READ WRITE YES SYS@ora12c> alter session set container=CDB$ROOT; Session altered. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ WRITE YES
--注意，此时种子容器必须处于read only状态。
SYS@ora12c> create pluggable database oracdb_pdb2 admin user pdb2_admin identified by admin file_name_convert = ('/u01/oracle/oradata/ora12c/pdbseed', '/u01/oracle/oradata/ora12c/cdb/pdb2'); Pluggable database created.
--需要先确定种子容器的数据文件存放路径，
--以及创建新的可插拔数据库的数据文件存放目录。
--如果使用OMF，则不需要设置file_name_convert参数。
SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ WRITE YES 4 ORACDB_PDB2 MOUNTED SYS@ora12c> alter pluggable database ORACDB_PDB2 open; Pluggable database altered. SYS@ora12c> show pdbs; CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 ORA12C_PDB1 READ WRITE YES 4 ORACDB_PDB2 READ WRITE NO SYS@ora12c> conn pdb2_admin/admin@ORACDB_PDB2; ERROR: ORA-12154: TNS:could not resolve the connect identifier specified Warning: You are no longer connected to ORACLE. @>
此时需要配置下tns了。
vi $ORACLE_HOME/network/admin/tnsnames.ora添加如下内容：
ORACDB_PDB2 = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = ora12)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = oracdb_pdb2) ) )
再看一下监听的状态：
[oracle@ora12 admin]$ lsnrctl services; LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 17-DEC-2015 10:14:04 Copyright (c) 1991, 2014, Oracle. All rights reserved. Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=ora12)(PORT=1521))) Services Summary... Service "ora12c" has 1 instance(s). Instance "ora12c", status READY, has 1 handler(s) for this service... Handler(s): "DEDICATED" established:1 refused:0 state:ready LOCAL SERVER Service "ora12cXDB" has 1 instance(s). Instance "ora12c", status READY, has 1 handler(s) for this service... Handler(s): "D000" established:0 refused:0 current:0 max:1022 state:ready DISPATCHER <machine: ora12.oracle.com, pid: 4585> (ADDRESS=(PROTOCOL=tcp)(HOST=ora12)(PORT=25789)) Service "ora12c_pdb1" has 1 instance(s). Instance "ora12c", status READY, has 1 handler(s) for this service... Handler(s): "DEDICATED" established:1 refused:0 state:ready LOCAL SERVER Service "oracdb_pdb2" has 1 instance(s). Instance "ora12c", status READY, has 1 handler(s) for this service... Handler(s): "DEDICATED" established:1 refused:0 state:ready LOCAL SERVER The command completed successfully
然后再测试一下：
SYS@ora12g> conn pdb2_admin/admin@ORACDB_PDB2; Connected.ok，好使了。
本文来自云栖社区合作伙伴“DBGEEK”
相关资源：Oracle Database 12c Release 2 Multitenant