Which three resources are always shared among CDB$ROOT and pluggable databases (PDBs)? (Choose three.)

Question

Options

• Athe data dictionary in CDB$ROOT
• Btemporary tablespaces
• Cthe Process Monitor Process (PMON)
• DSYSAUX tablespaces
• Ethe log writer process (LGWR)
• Fundo tablespaces

• A
  90% (37)
• B
  2% (1)
• D
  5% (2)
• F
  2% (1)

Explanation

In Oracle Multitenant architecture, background processes operate at the CDB instance level, not per-container - PMON (C) and LGWR (E) are single, instance-wide processes that serve CDB$ROOT and all PDBs simultaneously. The CDB$ROOT data dictionary (A) acts as the master catalog for the entire CDB, housing Oracle-supplied common objects that all PDBs reference; each PDB has only a local dictionary supplement, not its own full copy.

The distractors are wrong because each PDB owns its own copy of these tablespace types: SYSAUX (D) and TEMP (B) are required per-container and are never shared. Undo (F) is configurable - in local undo mode (the default since 19c), every PDB has its own undo tablespace, so it is not always shared.

Memory tip: Think "PILLs" for what PDBs keep locally - Process-independent things stay per-PDB (their own SYSAUX, TEMP, UNDO). What is shared is the instance backbone: processes (PMON, LGWR) and the root dictionary. If it's a background process or lives in CDB$ROOT, it's shared.

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