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说一说，如何解决附加的 PDB。

目前这个方法，还没有找到合理的解释：

执行

ALTER PLUGGABLE DATABASE APPLICATION ref_app SET COMPATIBILITY VERSION '1.1' ；

就可以删除掉这个奇怪的 PDB，也是很神奇了。

(这是我重新执行了前文探究 Oracle PDB Application Container (三)的动作，获得了新的PDB后的测试结果)

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         4 APPCON1                        READ WRITE NO         6 APPPDB1                        READ WRITE NO         8 F4127053456_3_1                READ WRITE NOSQL> SQL> alter session set container=appcon1; Session altered. SQL> ALTER PLUGGABLE DATABASE APPLICATION ref_app SET COMPATIBILITY VERSION '1.1'; Pluggable database altered. 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         4 APPCON1                        READ WRITE NO         6 APPPDB1                        READ WRITE NO <<<<<<<<<<< 上面的 F4127053456_3_1 PDB，消失不见了！ SQL>SQL> alter session set container=appcon1; Session altered. SQL>SQL> COLUMN app_name FORMAT A20COLUMN app_version FORMAT A10 SELECT app_name,       app_version,       app_statusFROM   dba_applicationsWHERE  app_name = 'REF_APP'; APP_NAME             APP_VERSIO APP_STATUS-------------------- ---------- ------------REF_APP              1.1        NORMAL SQL>

这个PDB 的数据文件也消失不见了。

SQL> select con_id, name from v$datafile order by con_id;     CON_ID----------NAME--------------------------------------------------------------------------------         4/refresh/home/cpdest/DB193CDB/BF761DFF522F4797E0538828410AB8E8/datafile/o1_mf_ref_app__j6xxvvs0_.dbf          4/refresh/home/cpdest/DB193CDB/BF761DFF522F4797E0538828410AB8E8/datafile/o1_mf_undotbs1_j6xxvcws_.dbf          4     CON_ID----------NAME--------------------------------------------------------------------------------/refresh/home/cpdest/DB193CDB/BF761DFF522F4797E0538828410AB8E8/datafile/o1_mf_sysaux_j6xxvcwq_.dbf          4/refresh/home/cpdest/DB193CDB/BF761DFF522F4797E0538828410AB8E8/datafile/o1_mf_system_j6xxvcwm_.dbf          6/refresh/home/cpdest/DB193CDB/BF761DFF52324797E0538828410AB8E8/datafile/o1_mf_un     CON_ID----------NAME--------------------------------------------------------------------------------dotbs1_j6xxvnwt_.dbf          6/refresh/home/cpdest/DB193CDB/BF761DFF52324797E0538828410AB8E8/datafile/o1_mf_sysaux_j6xxvnws_.dbf          6/refresh/home/cpdest/DB193CDB/BF761DFF52324797E0538828410AB8E8/datafile/o1_mf_ref_app__j6xxyygl_.dbf     CON_ID----------NAME--------------------------------------------------------------------------------          6/refresh/home/cpdest/DB193CDB/BF761DFF52324797E0538828410AB8E8/datafile/o1_mf_system_j6xxvnwr_.dbf 8 rows selected.
SQL>