Oracle 12c系列(二)|PDB的创建

时间:2022-05-05
本文章向大家介绍Oracle 12c系列(二)|PDB的创建,主要内容包括丨Clone a Local PDB、丨Creating a PDB by Cloning a Remote PDB、丨Creating a PDB by Cloning a Non-CDB、丨Cloning a PDB Without Cloning Its Data、基本概念、基础应用、原理机制和需要注意的事项等,并结合实例形式分析了其使用技巧,希望通过本文能帮助到大家理解应用这部分内容。
作者 杨禹航

出品 沃趣技术

PDB数据库的创建可以从现存的数据库中复制数据文件,包括种子容器、可插拔数据库、non-CDB数据库,创建时可以使用CREATE PLUGGABLE、RMAN、DBCA以及EM等。

在12.1版本中在创建PDB时,Source PDB必须处于read only状态,在12.2版本中,因为undo local mode新特性的推出,在创建PDB时,Source PDB在read write状态,依然可以创建。

另外在12.2版本中Oracle推出了refresh PDB特性,具有对Source PDB进行增量同步的功能。

使用CREATE PLUGGABLE命令可以使用以下资源创建PDB

  • CDB seed (PDB$SEED)
  • 克隆已经存在的PDB Local PDB Remote PDB
  • non-CDB数据库
  • 拔下的PDB

使用DBCA可以使用以下资源创建PDB

  • CDB seed (PDB$SEED)
  • RMAN备份
  • 拔下的PDB

示例:(这里只演示使用create pluggable database命令方式创建PDB)

使用CDB seed创建PDB

1.在SQL*Plus中输入CREATE PLUGGABLE DATABASE语句

(这里创建未ypdb1的pdb,管理用户为ypdb1)

CREATE PLUGGABLE DATABASE ypdb1 ADMIN USER ypdb1 IDENTIFIED BY oracle
STORAGE (MAXSIZE 2G)
DEFAULT TABLESPACE ypdb1
DATAFILE '/u01/app/oracle/oradata/ora12c/ypdb1/ypdb01.dbf' SIZE 100M AUTOEXTEND ON
PATH_PREFIX = '/u01/app/oracle/oradata/ora12c/ypdb1/'
FILE_NAME_CONVERT = ('/u01/app/oracle/oradata/ora12c/pdbseed', 
'/u01/app/oracle/oradata/ora12c/ypdb1');

ADMIN USER

用于执行管理任务的本地用户

STORAGE (MAXSIZE 2G)

指定了PDB可用的最大空间

DEFAULT TABLESPACE

为PDB指定默认的Tablespace

PATH_PREFIX

用来限制directory objects/Oracle XML/Create pfile/Oracle wallets所在的目录

FILE_NAME_CONVERT

设置子容器和数据文件副本的位置

2.语句执行完毕之后查看创建完成的PDB:

sys. ora12c>show pdbs
CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
     2 PDB$SEED                       READ ONLY  NO
     3 YPDB1                          MOUNTED
sys. ora12c>

克隆已经存在的PDB

这种方式可以通过使用当前CDB中的其他PDB,以及复制远端CDB中的PDB,还可以复制non-CDB数据库创建成PDB。

丨Clone a Local PDB

在Clone本地PDB时需要注意一下几点:

  • 使用的用户必须拥有’CREATE PLUGGABLE DATABASE’的权限(测试里使用sys用户)
  • 源PDB不可以是关闭状态
  • 如果CDB为shared undo,PDB必须为READ-ONLY状态
  • 如果CDB不是归档模式,那么PDB必须为READ-ONLY状态

说明:如果是Oracle Database 版本为12.1,那么PDB只能为READ-ONLY状态,因在12.1中undo模式,还只能选择shared undo。

sys. ora12c>show pdbs
CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
     2 PDB$SEED                       READ ONLY  NO
     3 YPDB1                          READ WRITE NO
sys. ora12c>

这里使用YPDB1做为源PDB,创建的PDB为YPDB2。

(1) 检查是否为shared undo模式

COL PROPERTY_NAME FOR A30
COL PROPERTY_VALUE FOR A30
SELECT property_name, property_value
FROM database_properties
WHERE property_name='LOCAL_UNDO_ENABLED';
PROPERTY_NAME                  PROPERTY_VALUE
------------------------------ ------------------------------
LOCAL_UNDO_ENABLED             TRUE

(2) 检查是否未archivelog模式

sys. ora12c>ARCHIVE LOG LIST
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /u01/app/oracle/recovery/ora12c/arch
Oldest online log sequence     21
Next log sequence to archive   23
Current log sequence           23
sys. ora12c>

(3) 创建验证数据

yangyuhang. ypdb1>CONN /AS SYSDBA
Connected.
sys. ora12c>conn yangyuhang/yangyuhang@ypdb1
Connected.
yangyuhang. ypdb1>SELECT COUNT(*) FROM t;
COUNT(*)
----------
 22198
Elapsed: 00:00:00.01
yangyuhang. ypdb1>

(4) 执行CREATE PLUGGABLE DATABASE语句(这里使用sys用户连接根容器)

CREATE PLUGGABLE DATABASE ypdb2 FROM ypdb1
PATH_PREFIX = '/u01/app/oracle/oradata/ora12c/ypdb2/'
FILE_NAME_CONVERT = ('/u01/app/oracle/oradata/ora12c/ypdb1/', '/u01/app/oracle/oradata/ora12c/ypdb2/')
SERVICE_NAME_CONVERT = ('ypdb1t','ypdb2t');

(5) 查看创建完成的YPDB2

sys. ora12c>show pdbs
CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
     2 PDB$SEED                       READ ONLY  NO
     3 YPDB1                          READ WRITE NO
     4 YPDB2                          MOUNTED
sys. ora12c>SELECT pdb_id, pdb_name, con_uid, status, creation_scn, con_id FROM cdb_pdbs;
PDB_ID PDB_NAME                CON_UID STATUS     CREATION_SCN     CON_ID
---------- -------------------- ---------- ---------- ------------ ----------
     2 PDB$SEED             1453953285 NORMAL              213          2
     3 YPDB1                2376019304 NORMAL           697945          3
     4 YPDB2                3908707960 NEW              707501          4
Elapsed: 00:00:00.02
sys. ora12c>

(6) 检查数据文件

sys. ora12c>ALTER PLUGGABLE DATABASE YPDB2 OPEN;
Pluggable database altered.
Elapsed: 00:00:14.02
sys. ora12c>SELECT con_id, tablespace_name, file_name FROM cdb_data_files WHERE con_id=4;
CON_ID TABLESP FILE_NAME
------ ------- ---------------------------------------------------------
 4 SYSTEM  /u01/app/oracle/oradata/ora12c/ypdb2/system01.dbf
 4 SYSAUX  /u01/app/oracle/oradata/ora12c/ypdb2/sysaux01.dbf
 4 DEFTBS  /u01/app/oracle/oradata/ora12c/ypdb2/deftbs01.dbf
 4 USERTBS /u01/app/oracle/oradata/ora12c/ypdb2/usertbs01.dbf
 4 UNDO_1  /u01/app/oracle/oradata/ora12c/ypdb2/system01_i1_undo.dbf
 4 YPDB1   /u01/app/oracle/oradata/ora12c/ypdb2/ypdb01.dbf
6 rows selected.
Elapsed: 00:00:00.01
sys. ora12c>

(7) 检查service_name

sys. ora12c>SELECT service_id, name, network_name, enabled, pdb, con_id FROM cdb_services;
SERVICE_ID NAME                NETWORK_NAME         ENA PDB           CON_ID
---------- ------------------- -------------------- --- --------- ----------
     1 SYS$BACKGROUND                           NO  CDB$ROOT           1
     2 SYS$USERS                                NO  CDB$ROOT           1
     3 ora12c.linux.com    ora12c.linux.com     NO  CDB$ROOT           1
     6 ypdb1.linux.com     ypdb1.linux.com      NO  YPDB1              3
     1 ypdb1t              ypdb1t               NO  YPDB1              3
     1 ypdb2t              ypdb2t               NO  YPDB2              4
     2 ypdb2.linux.com     ypdb2.linux.com      NO  YPDB2              4
7 rows selected.
Elapsed: 00:00:00.00
sys. ora12c>

源PDB中的service_name已经被更改指定的service_name.

(8) 检查验证数据

sys. ora12c>conn yangyuhang/yangyuhang@ypdb2
Connected.
yangyuhang. ypdb2>SELECT COUNT(*) FROM t;
COUNT(*)
----------
 22198
Elapsed: 00:00:00.11
yangyuhang. ypdb2>

丨Creating a PDB by Cloning a Remote PDB


Clone远端PDB时需要注意以下几点:

  • 如果PDB被Clone到的CDB的字符集不是AL32UTF8,那么源与目标字符集必须兼容。
  • 源端与目标端的字节顺序必须相同。
  • 连接的用户在CDB中必须拥有'CREATE PLUGGABLE DATABASE'的权限。
  • 源PDB不可以是关闭状态。
  • 如果远端CDB为shared undo,源PDB必须为READ-ONLY状态。
  • 如果远端CDB不是归档模式,源PDB必须为READ-ONLY状态。

这里测试将win平台ORA12CW中的PDB(ORA12CWPDB)复制到Linux的,目标PDB为PDB2。

(1) 查看源端与目标的字符集

col parameter for a30
col value for a30
select * from nls_database_parameters where parameter='NLS_CHARACTERSET'
or parameter='NLS_LANGUAGE' or parameter='NLS_NCHAR_CHARACTERSET';

(2) 查看源端与目标端字节顺序

col platform_name for a40
SELECT d.inst_id, t.platform_id, t.platform_name, t.endian_format, d.name FROM v$transportable_platform t, gv$database d
WHERE t.platform_name = d.platform_name;

(3) 查看源端归档模式

archive log list

(4) 查看源端undo模式

SELECT property_name, property_value
FROM database_properties
WHERE property_name='LOCAL_UNDO_ENABLED';

(5) 目标端创建dblink

CREATE DATABASE LINK ora12cw CONNECT TO system IDENTIFIED BY oracle USING 'ORA12CW';

(6) 运行CREATE PLUGGABLE DATABASE语句进行复制PDB

CREATE PLUGGABLE DATABASE pdb2 FROM ORA12CWPDB@ora12cw
PATH_PREFIX = '/u01/app/oracle/oradata/ora12cl/pdb2/'
FILE_NAME_CONVERT = ('D:U01APPORACLEORADATAORA12CWORA12CWPDB', '/u01/app/oracle/oradata/ora12cl/pdb2/');

(7) 创建完成后目标端查看PDB2

sys. ora12cl>show pdbs
CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
     2 PDB$SEED                       READ ONLY  NO
     4 PDB2                           MOUNTED
     5 PDB1                           MOUNTED
sys. ora12cl>SELECT pdb_id, pdb_name, con_uid, status, creation_scn, con_id FROM cdb_pdbs;
PDB_ID PDB_NAME                CON_UID STATUS     CREATION_SCN     CON_ID
---------- -------------------- ---------- ---------- ------------ ----------
     2 PDB$SEED             3409233005 NORMAL          1408788          2
     4 PDB2                 2218727525 NEW             1824437          4
     5 PDB1                 1058019921 NORMAL          1535445          5
Elapsed: 00:00:00.00
sys. ora12cl>

(8) 目标查看数据文件

sys. ora12cl>alter pluggable database pdb2 open;
Pluggable database altered.
Elapsed: 00:00:14.02
sys. ora12cl>SELECT con_id, tablespace_name, file_name FROM cdb_data_files WHERE con_id=4;
CON_ID TABLESPACE_NAME FILE_NAME
------ --------------- --------------------------------------------------
 4 SYSTEM          /u01/app/oracle/oradata/ora12cl/pdb2/SYSTEM01.DBF
 4 SYSAUX          /u01/app/oracle/oradata/ora12cl/pdb2/SYSAUX01.DBF
 4 UNDOTBS1        /u01/app/oracle/oradata/ora12cl/pdb2/UNDOTBS01.DBF
 4 USERS           /u01/app/oracle/oradata/ora12cl/pdb2/USERS01.DBF
Elapsed: 00:00:00.00
sys. ora12cl>

克隆远端的PDB成功。

丨Creating a PDB by Cloning a Non-CDB


Clone远端的non-CDB时需要注意以下几点:

  • 连接的用户必须拥有'CREATE PLUGGABLE DATABASE'的权限。
  • non-CDB不可以是关闭状态。
  • 如果远端non-CDB不是归档模式,那么non-CDB必须为READ-ONLY状态。
  • 源端与目标端的字节序必须相同。
  • 如果创建的PDB来自于non-CDB,那么non-CDB的版本必须在12.1.0.2之后。
  • 如果创建的PDB来自于non-CDB,当PDB创建完成后使用SYSDBA权限用户登录PDB运行noncdb_to_pdb.sql脚本,将这里将源端non-CDB数据库orcl12复制到ora12cl中,命名为PDB3。

(1)查看non-CDB数据库版本

SELECT * FROM v$version;
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

(2)查看远端non-CDB数据库模式

SELECT dbid, name, open_mode, cdb FROM v$database;
  DBID NAME      OPEN_MODE            CDB
---------- --------- -------------------- ---
3544959965 ORCL12    READ WRITE           NO

(3)查看non-CDB数据库是否为归档模式

ARCHIVE LOG LIST

(4)查看源端与目标端字节顺序

col platform_name for a40
SELECT d.inst_id, t.platform_id, t.platform_name, t.endian_format, d.name FROM v$transportable_platform t, gv$database d
WHERE t.platform_name = d.platform_name;

(5)目标端创建dblink

CREATE DATABASE LINK orcl12 CONNECT TO system IDENTIFIED BY oracle USING 'ORCL12';

(6)执行CREATE PLUGGABLE DATABASE语句

CREATE PLUGGABLE DATABASE pdb3 FROM orcl12@orcl12
PATH_PREFIX = '/u01/app/oracle/oradata/ora12cl/pdb3/'
FILE_NAME_CONVERT = ('/u01/app/oracle/oradata/orcl12/', '/u01/app/oracle/oradata/ora12cl/pdb3/');

(7)PDB创建成功后查看PDB

sys. ora12cl>show pdbs
CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
     2 PDB$SEED                       READ ONLY  NO
     3 PDB3                           MOUNTED
     4 PDB2                           READ WRITE NO
     5 PDB1                           MOUNTED
sys. ora12cl>SELECT pdb_id, pdb_name, con_uid, status, creation_scn, con_id FROM cdb_pdbs;
PDB_ID PDB_NAME           CON_UID STATUS     CREATION_SCN     CON_ID
---------- --------------- ---------- ---------- ------------ ----------
     3 PDB3            3564415452 NEW             3014651          3
     2 PDB$SEED        3409233005 NORMAL          1408788          2
     4 PDB2            2218727525 NORMAL          1824437          4
     5 PDB1            1058019921 NORMAL          1535445          5
Elapsed: 00:00:00.00

(8)运行noncdb_to_pdb.sql脚本(必须使用拥有SYSDBA权限的用户在PDB中执行)

$ORACLE_HOME/rdbms/admin/noncdb_to_pdb.sql

(9)查看数据文件

sys. ora12cl>alter pluggable database pdb3 open;
Pluggable database altered.
Elapsed: 00:00:52.88
sys. ora12cl>SELECT con_id, tablespace_name, file_name FROM cdb_data_files WHERE con_id=3;
CON_ID TABLESPACE_NAME FILE_NAME
---------- --------------- --------------------------------------------------
     3 SYSTEM          /u01/app/oracle/oradata/ora12cl/pdb3/system01.dbf
     3 SYSAUX          /u01/app/oracle/oradata/ora12cl/pdb3/sysaux01.dbf
     3 UNDOTBS1        /u01/app/oracle/oradata/ora12cl/pdb3/undotbs01.dbf
     3 USERS           /u01/app/oracle/oradata/ora12cl/pdb3/users01.dbf
Elapsed: 00:00:00.00
sys. ora12cl>

丨Cloning a PDB Without Cloning Its Data

在克隆已有的PDB或者non CDB时,我们也可以将克隆语句中加入NO DATA子句,在使用NO DATA子句时,仅仅会克隆源PDB中的模型定义,并不会克隆PDB中的数据。(Oracle数据库内自动创建的schemas下的对象会被成功克隆,而用户创建的schemas下的对象仅仅会克隆对象的定义结构)。

测试克隆本地PDB时使用no data子句

这里将WOQUPDB克隆为PDBTEST.

(1)源PDB

sys. woqu>show pdbs
CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
     2 PDB$SEED                       READ ONLY  NO
     3 WOQUPDB                        READ WRITE NO
sys. woqu>COL PROPERTY_NAME FOR A30
sys. woqu>COL PROPERTY_VALUE FOR A30
sys. woqu>

(2)检查UNDO模式及归档模式

sys. woqu>SELECT property_name, property_value
2  FROM database_properties
3  WHERE property_name='LOCAL_UNDO_ENABLED';
PROPERTY_NAME                  PROPERTY_VALUE
------------------------------ ------------------------------
LOCAL_UNDO_ENABLED             TRUE
Elapsed: 00:00:00.04
sys. woqu>sys. woqu>archive log list
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     7
Next log sequence to archive   9
Current log sequence           9
sys. woqu> 

(3)创建测试数据表t,注意这里的t表位于sys用户下

05:51:10 sys. woqupdb>create table t as select * from dba_objects where rownum<=10;
Table created.
Elapsed: 00:00:00.10
05:52:41 sys. woqupdb>select count(*) from t;
COUNT(*)
----------
    10
Elapsed: 00:00:00.01
05:52:50 sys. woqupdb>

表t中共有10条数据。

(4)创建测试数据表t_tab,注意这里的t表位于yangyuhang用户下

05:51:46 yangyuhang. woqupdb>create table t_tab as select * from dba_objects where rownum<=999;
Table created.
Elapsed: 00:00:01.84
05:52:15 yangyuhang. woqupdb>select count(*) from t_tab;
COUNT(*)
----------
   999
Elapsed: 00:00:00.01
05:52:19 yangyuhang. woqupdb>

(5)使用create pluggable database + NO DATA子句创建pdb:pdbtest

sys. woqu>CREATE PLUGGABLE DATABASE pdbtest FROM woqupdb NO DATA
2  PATH_PREFIX = '/u01/app/oracle/oradata/woqu/pdbtest'
3  FILE_NAME_CONVERT = ('/u01/app/oracle/oradata/woqu/woqupdb', '/u01/app/oracle/oradata/woqu/pdbtest');
Pluggable database created.
Elapsed: 00:00:09.35
sys. woqu>

(6)检查克隆完成的pdbtest

sys. woqu>show pdbs
CON_ID CON_NAME    OPEN MODE  RESTRICTED
---------- ----------- ---------- ----------
     2 PDB$SEED    READ ONLY  NO
     3 WOQUPDB     READ WRITE NO
     5 PDBTEST     MOUNTED
sys. woqu>SELECT pdb_id, pdb_name, con_uid, status, creation_scn, con_id FROM cdb_pdbs;
PDB_ID PDB_NAME       CON_UID STATUS     CREATION_SCN     CON_ID
---------- ----------- ---------- ---------- ------------ ----------
     3 WOQUPDB     1167267009 NORMAL          1443334          3
     2 PDB$SEED     399989944 NORMAL          1408751          2
     5 PDBTEST     3356573055 NEW             1956581          5
Elapsed: 00:00:00.05
sys. woqu>alter pluggable database pdbtest open;
Pluggable database altered.
Elapsed: 00:00:07.09
sys. woqu>show pdbs
CON_ID CON_NAME    OPEN MODE  RESTRICTED
---------- ----------- ---------- ----------
     2 PDB$SEED    READ ONLY  NO
     3 WOQUPDB     READ WRITE NO
     5 PDBTEST     READ WRITE NO
sys. woqu>SELECT pdb_id, pdb_name, con_uid, status, creation_scn, con_id FROM cdb_pdbs;
PDB_ID PDB_NAME     CON_UID STATUS CREATION_SCN     CON_ID
---------- --------- ---------- ------ ------------ ----------
     3 WOQUPDB   1167267009 NORMAL      1443334          3
     2 PDB$SEED   399989944 NORMAL      1408751          2
     5 PDBTEST   3356573055 NORMAL      1956581          5
Elapsed: 00:00:00.02
sys. woqu>

(7)将从测试数据

sys. woqu>alter session set container=pdbtest;
Session altered.
Elapsed: 00:00:00.07
sys. woqu>show user con_id
USER is "SYS"
CON_ID
------------------------------
5
sys. woqu>select count(*) from t;
COUNT(*)
----------
    10
Elapsed: 00:00:00.00
sys. woqu>select count(*) from yangyuhang.t_tab;
COUNT(*)
----------
     0
Elapsed: 00:00:00.02
sys. woqu>

通过测试可以看到sys下的对象中的数据依然克隆成功,而自建用户下的对象中数据并没有跟着一起克隆。

测试克隆远端PDB时使用no data子句

这里将远端PDB:PDBTEST克隆到本地,命名为ORA12CPDB2:

(1)创建DBLINK

sys. ora12c>CREATE DATABASE LINK woqu CONNECT TO system IDENTIFIED BY oracle USING 'WOQU';
Database link created.
Elapsed: 00:00:00.15
sys. ora12c>

(2)克隆PDBTEST

sys. ora12c>CREATE PLUGGABLE DATABASE ORA12CPDB2 FROM PDBTEST@WOQU NO DATA
2    PATH_PREFIX = '/u01/app/oracle/oradata/ora12c/ora12cpdb2'
3    FILE_NAME_CONVERT = ('/u01/app/oracle/oradata/woqu/pdbtest', '/u01/app/oracle/oradata/ora12c/ora12cpdb2');
Pluggable database created.
Elapsed: 00:00:10.44
sys. ora12c>

(3)检查克隆完成后的ORA12CPDB2

sys. ora12c>show pdbs
CON_ID CON_NAME       OPEN MODE  RESTRICTED
---------- -------------- ---------- ----------
     2 PDB$SEED       READ ONLY  NO
     3 ORA12CPDB      READ WRITE NO
     5 ORA12CPDB2     MOUNTED
sys. ora12c>SELECT pdb_id, pdb_name, con_uid, status, creation_scn, con_id FROM cdb_pdbs;
PDB_ID PDB_NAME         CON_UID STATUS     CREATION_SCN     CON_ID
---------- ------------- ---------- ---------- ------------ ----------
     3 ORA12CPDB     1788418398 NORMAL          1442734          3
     2 PDB$SEED      2375660446 NORMAL          1408749          2
     5 ORA12CPDB2    2003741801 NEW             1959473          5
Elapsed: 00:00:00.01
sys. ora12c>

(4)验证数据

sys. ora12c>alter pluggable database ora12cpdb2 open;
Pluggable database altered.
Elapsed: 00:00:05.24
sys. ora12c>alter session set container=ora12cpdb2;
Session altered.
Elapsed: 00:00:00.04
sys. ora12c>select count(*) from t;
COUNT(*)
----------
    10
Elapsed: 00:00:00.01
sys. ora12c>select count(*) from yangyuhang.t_tab;
COUNT(*)
----------
     0
Elapsed: 00:00:00.00
sys. ora12c>