Multitenant Architecture Flashcards

Which clause must be included in the CREATE DATABASE statement to create a Container Database (CDB)?

Answer: ENABLE PLUGGABLE DATABASE

The ENABLE PLUGGABLE DATABASE clause in CREATE DATABASE instructs Oracle to create a CDB rather than a traditional non-CDB.

Which SQL statement opens all PDBs in a CDB at once?

Answer: ALTER PLUGGABLE DATABASE ALL OPEN

ALTER PLUGGABLE DATABASE ALL OPEN opens every PDB in the current CDB instance in a single command.

After restarting a CDB, what is the default state of user-created PDBs?

Answer: MOUNTED

When a CDB restarts, all PDBs default to MOUNTED state and must be explicitly opened unless SAVE STATE was previously configured.

Which command creates a new PDB from the PDB$SEED template?

Answer: CREATE PLUGGABLE DATABASE new_pdb ADMIN USER pdb_admin IDENTIFIED BY password

CREATE PLUGGABLE DATABASE with the ADMIN USER clause creates a new PDB using PDB$SEED as the source template.

What does the CONTAINERS() table function allow a DBA to do when connected to CDB$ROOT?

Answer: Query a specific table across all open PDBs simultaneously

The CONTAINERS() function enables cross-container queries, allowing a single SELECT to retrieve data from a table across all open PDBs.

What happens to all PDBs when a DBA shuts down the CDB instance?

Answer: All PDBs are automatically closed along with the CDB

PDBs share the CDB instance, so shutting down the CDB instance closes all PDBs — they cannot run independently.

Which view should be queried to check the real-time OPEN_MODE of all PDBs in a CDB?

Answer: V$PDBS

V$PDBS is a dynamic performance view that reflects the current OPEN_MODE (READ WRITE, READ ONLY, or MOUNTED) of each PDB.