[Oracle 工程师手记]探究 Oracle PDB Application Container (三)

继续来研究 application container 中的 application 升级问题。

首先，生成 application container 和 application pdb  ，以及 application：

 

alter system set db_create_file_dest='/refresh/home/cpdest';
CREATE PLUGGABLE DATABASE appcon1 AS APPLICATION CONTAINER ADMIN USER app_admin IDENTIFIED BY Password1;
 
ALTER PLUGGABLE DATABASE appcon1 OPEN;
ALTER SESSION SET container = appcon1;
 
CREATE PLUGGABLE DATABASE apppdb1 ADMIN USER pdb_admin IDENTIFIED BY Password1;
ALTER PLUGGABLE DATABASE apppdb1 OPEN;
 
 
ALTER SESSION SET container = appcon1;
ALTER PLUGGABLE DATABASE APPLICATION ref_app BEGIN INSTALL '1.0';
 
 
CREATE TABLESPACE ref_app_ts DATAFILE SIZE 1M AUTOEXTEND ON NEXT 1M;
 
CREATE USER ref_app_user IDENTIFIED BY ref_app_user
  DEFAULT TABLESPACE ref_app_ts
  QUOTA UNLIMITED ON ref_app_ts
  CONTAINER=ALL;
 
GRANT CREATE SESSION, CREATE TABLE TO ref_app_user;
 
CREATE TABLE ref_app_user.reference_data SHARING=DATA (
  id          NUMBER,
  description VARCHAR2(50),
  CONSTRAINT t1_pk PRIMARY KEY (id)
);
 
INSERT INTO ref_app_user.reference_data
SELECT level,
       'Description of ' || level
FROM   dual
CONNECT by level <= 5;
COMMIT;
 
 
ALTER PLUGGABLE DATABASE APPLICATION ref_app END INSTALL;

 
第一次的 application upgrade:

ALTER SESSION SET container = appcon1;
 
ALTER PLUGGABLE DATABASE APPLICATION ref_app BEGIN UPGRADE '1.0' TO '1.1';
 
create table tab001(id integer, val varchar2(3));

ALTER PLUGGABLE DATABASE APPLICATION ref_app END UPGRADE;

 可以，看到生成了一个特殊的 PDB:  F139230267_3_1

SQL> alter session set container=cdb$root;

Session altered.

SQL> show pdbs;

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB193                         MOUNTED
         7 APPCON1                        READ WRITE NO
         9 APPPDB1                        READ WRITE NO
        11 F139230267_3_1                 READ WRITE NO
SQL>

 
第二次的 application upgrade:

ALTER SESSION SET container = appcon1;
 
ALTER PLUGGABLE DATABASE APPLICATION ref_app BEGIN UPGRADE '1.1' TO '1.2';
 
create table tab002(id integer, val varchar2(3));

ALTER PLUGGABLE DATABASE APPLICATION ref_app END UPGRADE;

 又生成了 一个 特殊PDB:  F139230267_3_2

 

SQL> alter session set container=cdb$root;

Session altered.

SQL> show pdbs;

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB193                         MOUNTED
         6 F139230267_3_2                 READ WRITE NO
         7 APPCON1                        READ WRITE NO
         9 APPPDB1                        READ WRITE NO
        11 F139230267_3_1                 READ WRITE NO
SQL>

 
第三次的 application upgrade:

ALTER SESSION SET container = appcon1;
 
ALTER PLUGGABLE DATABASE APPLICATION ref_app BEGIN UPGRADE '1.2' TO '1.3';
 
create table tab003(id integer, val varchar2(3));

ALTER PLUGGABLE DATABASE APPLICATION ref_app END UPGRADE;

 

再次生成特殊的 PDB:

SQL> alter session set container=cdb$root;

Session altered.

SQL> show pdbs;

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB193                         MOUNTED
         5 F139230267_3_3                 READ WRITE NO
         6 F139230267_3_2                 READ WRITE NO
         7 APPCON1                        READ WRITE NO
         9 APPPDB1                        READ WRITE NO
        11 F139230267_3_1                 READ WRITE NO
SQL>

每一次升级 application ，都生成一个新PDB，每次大约 0.7 GB， 对空间的浪费太大了。

SQL> select sum(bytes)/1024/1024/1024 from v$datafile where con_id=11;

SUM(BYTES)/1024/1024/1024
-------------------------
               .684570313

SQL> select sum(bytes)/1024/1024/1024 from v$datafile where con_id=6;

SUM(BYTES)/1024/1024/1024
-------------------------
               .694335938

SQL>

SQL> select sum(bytes)/1024/1024/1024 from v$datafile where con_id=5;

SUM(BYTES)/1024/1024/1024
-------------------------
               .694335938

SQL>

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