新特性：CDB/PDB的维护命令：如何删除PDB（生产环境慎用）

SQL> show pdbs  

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1_WHS                       READ WRITE NO
         4 PDB2_WHS                       READ WRITE NO
SQL> alter pluggable database PDB2_WHS close immediate;

Pluggable database altered.

SQL> drop pluggable database PDB2_WHS including datafiles;

Pluggable database dropped.

SQL> show pdbs 

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1_WHS                       READ WRITE NO