Before Version 12.1.0.2 whenever a container database was started all the pluggable databases associated with container database remains in MOUNT state. The workaround was to write a database startup trigger to open PDB during container startup. A Basic example can found on MOS Note: 1594901.1 12c Pluggable Database is closed on restart of Computer
If you prefer a more dynamic method my colleague has written a blog post Database 12c: Pluggable database autostart like HAS
Beginning with 12.1.0.2 this feature can be achieved with the PDB save state Feature
For example CRMDB needs to be open after the container database restarts and the HRDB can be in mount state
SQL> show pdbs CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 HRDB READ WRITE NO 4 CRMDB MOUNTED
We issue the save command in the current state „MOUNT“ for the CRMDB database.
SQL> alter pluggable database CRMDB save state; Pluggable database altered.
When we restart the Container database all pluggable databases are in MOUNT state. This is right because we saved the MOUNT state.
SQL> show pdbs CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 HRDB MOUNTED 4 CRMDB MOUNTED
We do the same, but first we open the CRMDB pluggable database in READ WRITE state.
SQL> alter pluggable database CRMDB open; Pluggable database altered. SQL> alter pluggable database CRMDB save state; Pluggable database altered.
And now after the container database restarts, the CRMDB is in the expected state.
SQL> show pdbs CON_ID CON_NAME OPEN MODE RESTRICTED ---------- ------------------------------ ---------- ---------- 2 PDB$SEED READ ONLY NO 3 HRDB MOUNTED 4 CRMDB READ WRITE NO
Hope this was helpfully
