改变PDB大小
SQL> show pdbs
CON_ID CON_NAME OPEN MODE RESTRICTED

     2 PDB$SEED                       READ ONLY  NO
     3 PDBTEST                        MOUNTED
     4 CLONEPDB_PLUG                  MOUNTED

SQL> ALTER PLUGGABLE DATABASE STORAGE(MAXSIZE UNLIMITED);
ALTER PLUGGABLE DATABASE STORAGE(MAXSIZE UNLIMITED)
*
第 1 行出现错误:
ORA-65046: 不允许从可插入数据库外部执行该操作
SQL> alter session set container=PDBTEST;
会话已更改。

SQL> ALTER PLUGGABLE DATABASE STORAGE(MAXSIZE UNLIMITED);
ALTER PLUGGABLE DATABASE STORAGE(MAXSIZE UNLIMITED) *
第 1 行出现错误:
ORA-01219: 数据库或可插入数据库未打开: 仅允许在固定表或视图中查询

SQL> startup 插接式数据库已打开。
SQL> show pdbs

CON_ID CON_NAME                       OPEN MODE  RESTRICTED                                                         ---------- ------------------------------ ---------- ----------
     3 PDBTEST                        READ WRITE NO

SQL> ALTER PLUGGABLE DATABASE STORAGE(MAXSIZE UNLIMITED);

插接式数据库已变更。

SQL> alter session set container=CDB$ROOT;

会话已更改。

SQL> SELECT SYS_CONTEXT ('USERENV', 'CON_NAME') FROM DUAL;

SYS_CONTEXT('USERENV','CON_NAME')

CDB$ROOT

SQL> show pdbs

CON_ID CON_NAME                       OPEN MODE  RESTRICTED

     2 PDB$SEED                       READ ONLY  NO
     3 PDBTEST                        READ WRITE NO
     4 CLONEPDB_PLUG                  MOUNTED