Oracle 12c: Starting and Stopping PDB

In this article we will learn how to start and stop 12c database having multitenant databases.
For shutting down and starting container database, method is same as standalone database like 11g. Connect to container database(cdb$root) with sysdba and check the status of PDB's
SQL> show pdbs

    CON_ID CON_NAME                  OPEN MODE  RESTRICTED

---------- -------------------------- ---------- ----------

         2 PDB$SEED                       READ ONLY  NO

         3 PDB_1                          READ WRITE NO

         4 PDB_TECHON                     READ WRITE NO

Here we can see pdbs are in read only and read write mode. first check where we are, whether in PDB or CDB

SQL> show con_name

CON_NAME

------------------------------

CDB$ROOT

SQL>

We are in root container. Now will shutdown one of the pluggable database PDB_TECHON
Below is command we use to stop and start pluggable database

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED

---------- ------------------------------ ---------- ----------

         2 PDB$SEED                       READ ONLY  NO

         3 PDB_1                          READ WRITE NO

         4 PDB_TECHON                     READ WRITE NO

SQL> alter  pluggable database PDB_TECHON close;

Pluggable database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED

---------- ------------------------------ ---------- ----------

         2 PDB$SEED                       READ ONLY  NO

         3 PDB_1                          READ WRITE NO

         4 PDB_TECHON                     MOUNTED

SQL> 

Whenever we start container database, container database(CDB$ROOT) will be opened in read write mode and all PDB's will be in MOUNTED state and default SEED database will always be in READ only mode.

Now will be start our PDB from container database

SQL> show con_name

CON_NAME

------------------------------

CDB$ROOT

SQL>

SQL> alter pluggable database PDB_TECHON open;

Pluggable database altered.

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED

---------- ------------------------------ ---------- ----------

         2 PDB$SEED                       READ ONLY  NO

         3 PDB_1                          READ WRITE NO

         4 PDB_TECHON                     READ WRITE NO

SQL>

Now perform the same operations from particular PDB (PDB_TECHON). first we need switch to pluggable database using alter session command. We do not need to mentioned pluggable database name while start and stop

Now switch back to container database and check the status of all PDB's

SQL> alter session set container=CDB$ROOT;

Session altered.

SQL>

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED

---------- ------------------------------ ---------- ----------

         2 PDB$SEED                       READ ONLY  NO

         3 PDBGD                          READ WRITE NO

         4 PDB_TECHON                     READ WRITE NO

SQL>