Hidden Parameters in Oracle AI Database 26ai H.11 Multitenant (PDB/CDB) (95)

 

Name	Type	Value	At default?	Level	PDB	RAC inst.	Flags	Description
_cdb_compatible	Boolean	TRUE	yes	STATIC	N	N		CDB Compatible
_cdb_cross_container	Integer	65535	yes	SESSION	Y	Y		Debug flag for cross container operations
_cdb_disable_pdb_limit	Boolean	FALSE	yes	STATIC	N	N		CDB Compatible
_cdb_fleet_sync_timeout	Integer	10	yes	SYSTEM imm.	N	Y		Time in minutes to wait for sync of stub entry in CDB Fleet
_cdb_init_batch_size	Integer	100	yes	SESSION	Y	Y		Batch size for reading pdb info during CDB mount
_cdb_port	Integer	0	yes	SYSTEM imm.	N	Y		Port number for CDB Servlet
_cdb_rac_affinity	Boolean	TRUE	yes	SESSION	Y	Y		rac affinity for parallel cdb operations
_cdb_special_old_xplan	Boolean	FALSE	yes	SESSION	Y	Y		display old-style plan for CDB special fixed table
_cdb_spfile_inherit	Boolean	FALSE	yes	STATIC	Y	N		Inherit CDB Spfile enabled/disabled in a PDB
_cdb_svlt_use_tcps	Boolean	FALSE	yes	SYSTEM imm.	N	N		Use TCPS for CDB Servlet
_cdb_view_no_skip_migrate	Boolean	FALSE	yes	SESSION	Y	Y		do not skip OPEN MIGRATE PDBs from results of CONTAINERS()
_cdb_view_no_skip_restricted	Boolean	FALSE	yes	SESSION	Y	Y		do not skip RESTRICTED mode PDBs from results of CONTAINERS()
_cdb_view_parallel_degree	Integer	65535	yes	SESSION	Y	Y		Parallel degree for a CDB view query
_cdb_view_prefetch_batch_size	Integer	200	yes	SESSION	Y	Y		Batch Size for Prefetch for a CDB view query
_cdb_view_rc_shelflife	Integer	30	yes	SESSION	Y	Y		Result Cache Shelflife for a CDB view query
_cdb_view_recursive_px_enabled	Boolean	TRUE	yes	SESSION	Y	Y		enable parallelism of recursive SQL under CONTAINERS()
_cdb_view_serial_ok	Boolean	FALSE	yes	SESSION	Y	Y		is serial OK for cross-container
_pdb_auto_save_state	Boolean	FALSE	yes	SYSTEM imm.	N	Y		Save pdb state automatically on state change on a given instance
_pdb_auto_undots_create_off	Boolean	FALSE	yes	SESSION	Y	Y		disable automatic creation of undo tablespace in local undo mode
_pdb_char_set_intconv	Boolean	FALSE	yes	SESSION	Y	Y		Enforce internal_convert for PDB character set conversion
_pdb_clone_preserve_guid	Boolean	FALSE	yes	SESSION	N	N		Use same guid for a pdb clone
_pdb_close_force_kill_session	Integer	1	yes	SESSION	Y	Y		Force kill sessions during PDB close
_pdb_close_immediate_kill_batchsize	Integer	1000	yes	SESSION	N	N		batch size for killing sessions inside the PDB
_pdb_cluster_database	Boolean	TRUE	yes	STATIC	Y	N		This parameter can be turned-off when cluster_database is TRUE
_pdb_component_violation_restricted	String		yes	SYSTEM imm.	N	Y		Components allowed to have mismatch between CDB$Root and PDB
_pdb_create_use_sysoper_conn	Boolean	FALSE	yes	SESSION	Y	Y		spread file copy slaves across instances
_pdb_datapatch_violation_restricted	Boolean	TRUE	yes	SESSION	Y	Y		Open pdb in restricted mode for datapatch error violation
_pdb_enable_staging_tables	Boolean	FALSE	yes	SESSION	Y	Y		Enable the use of staging objects within the PDB
_pdb_exclude_tablespace_for_metaclone	String		yes	SESSION	Y	Y		Internally exclude tablespaces for metadata refresh clones
_pdb_exclude_tslist_for_logging	String		yes	SESSION	Y	Y		List of tablespaces excluded from force logging
_pdb_failure_testing	Integer	0	yes	SESSION	Y	Y		Testing failure in pluggable database related operations
_pdb_file_copy_affinitize	Boolean	FALSE	yes	SESSION	Y	Y		spread file copy slaves across instances
_pdb_file_copy_buffers	Integer	8	yes	SESSION	Y	Y		number of buffers to use for pdb file copy
_pdb_first_script	Boolean	FALSE	yes	SESSION	N	N		Running a script that is PDB-first/ROOT-last
_pdb_force_cfd	Boolean	FALSE	yes	SYSTEM imm.	Y	Y		Force DB_CREATE_FILE_DEST path for all datafiles in PDB
_pdb_hash_table_latches	Integer	16	yes	STATIC	N	N		number of PDB hash table latches
_pdb_hash_table_size	Integer	255	yes	STATIC	N	N		number of buckets in PDB hash table
_pdb_hybrid_read_only	Boolean	FALSE	yes	SYSTEM imm.	Y	Y		Hybrid read only mode allows CDB common user to patch the PDB
_pdb_ignore_table_clauses	Boolean	TRUE	yes	SESSION	Y	Y		Ignore subset of clauses in CREATE TABLE and ALTER TABLE
_pdb_inherit_cfd	Boolean	FALSE	yes	SYSTEM imm.	Y	Y		Automatically enable CREATE_FILE_DEST clause in the PDB
_pdb_isolation_class	String	NONE	yes	STATIC	N	N		PDB isolation level: NONE, HIGH or MAX
_pdb_ktg_buffer_size	Integer	16	yes	SESSION	Y	Y		KTG buffer size (in KB) to store inmemory traces
_pdb_ldp_cascade	Integer	0	yes	SESSION	Y	Y		pluggable database lockdown profile cascade param
_pdb_lifespan_callout	String		yes	SESSION	Y	Y		PL SQL Procedure to import lifespan
_pdb_lifespan_skip_pseudo_open_close	Boolean	FALSE	yes	SESSION	Y	Y		Skip pseudo open/close for lifespan update during role transition
_pdb_live_replay_bind_table	String		yes	SESSION	Y	N		cloud table name to record bind info
_pdb_live_replay_error_table	String		yes	SESSION	Y	N		table name to record error info
_pdb_live_replay_sess_table	String		yes	SESSION	Y	N		cloud table name to record session info
_pdb_live_replay_stmt_table	String		yes	SESSION	Y	N		cloud table name to record statement info
_pdb_live_replay_temp_table	String		yes	SESSION	Y	N		table name to record temp info
_pdb_local_undo_tablespace_init_size	Big integer	100000000	yes	SESSION	Y	Y		Initial size for undo tablespace
_pdb_lockdown_bypass_sr	Big integer	0	yes	SESSION	Y	Y		special run lockdown parameter
_pdb_lockdown_ddl_clauses	Big integer	0	yes	SESSION	Y	Y		pluggable database lockdown clauses for statements
_pdb_lockdown_error_message	Boolean	FALSE	yes	SESSION	Y	Y		Enable pdb lockdown specific error message
_pdb_lrg_auto_undots_create	Boolean	FALSE	yes	STATIC	N	N		enable automatic creation of undo tablespace in local undo mode
_pdb_mask_cdb_info	Boolean	FALSE	yes	SYSTEM imm.	N	Y		Enable masking CDB information within a PDB
_pdb_max_audit_size	Big integer	0	yes	SESSION	Y	Y		Default value for MAX_AUDIT_SIZE property in new PDB creation
_pdb_max_diag_size	Big integer	0	yes	SESSION	Y	Y		Default value for MAX_DIAG_SIZE property in new PDB creation
_pdb_max_protection_mode	Boolean	FALSE	yes	SESSION	Y	Y		Prevent data loss when database switches to Max Performance mode
_pdb_max_size_discount	Integer	10	yes	SESSION	Y	Y		Discount percentable on PDB Max space usage
_pdb_media_rcv_parallelism	Integer	0	yes	SESSION	Y	Y		PDB media recovery parallelism
_pdb_name_case_sensitive	Boolean	FALSE	yes	STATIC	N	N		Keeps PDB name case sensitive
_pdb_oper_trace_threshold	Integer	600	yes	SESSION	Y	Y		PDB operations timing trace threshold
_pdb_oper_trace_threshold_softassert	Boolean	FALSE	yes	SESSION	Y	Y		PDB operations timing threshold soft assert
_pdb_read_only_refresh	Boolean	FALSE	yes	SESSION	Y	Y		allow refresh when pdb is open r/o
_pdb_refresh_apply_available_redo	Boolean	FALSE	yes	SESSION	Y	Y		apply all available redo for pdb refresh
_pdb_refresh_apply_master_key_rekey	Boolean	TRUE	yes	SESSION	Y	Y		Apply master rekey marker during pdb refresh
_pdb_refresh_log_info_callout	String		yes	SESSION	Y	Y		PL SQL Procedure to get log info
_pdb_refresh_quiesce_use_restricted_open	Boolean	FALSE	yes	SESSION	Y	Y		open source in restricted mode during ref clone activation
_pdb_refresh_remote_logs_baseuri	String		yes	SESSION	Y	Y		Location of archive logs to use for pdb refresh
_pdb_refresh_remote_logs_path	String		yes	SESSION	Y	Y		Location of archive logs to use for pdb refresh
_pdb_refresh_remote_logs_trackdb	String		yes	SESSION	Y	Y		Location of json trackdb for scn->seq# mapping
_pdb_refresh_restrict_until_point	Boolean	FALSE	yes	SESSION	Y	Y		restrict until scn/time for pdb refresh
_pdb_refresh_scn_to_seq_exttbl	String		yes	SESSION	Y	N		external table name to use convert scn to thread#,seq#
_pdb_refresh_temp_files_autoextend_size	Big integer	104857600	yes	SYSTEM imm.	N	Y		refreshable clones temp files autoextend size
_pdb_refresh_use_dblink_to_catalog	Boolean	FALSE	yes	SESSION	Y	Y		Use central catalog for pdb refresh
_pdb_refresh_use_local_logs	Boolean	TRUE	yes	SESSION	Y	Y		Use local logs for pdb refresh
_pdb_relocate_read_only_open	Boolean	TRUE	yes	SESSION	Y	Y		Open PDB is read only mode during a PDB Relocate
_pdb_replay_param_allowlist	String		yes	SYSTEM imm.	N	Y		pdb replay parameter allow list
_pdb_replay_param_blocklist	String		yes	SYSTEM imm.	N	Y		pdb replay parameter block list
_pdb_replay_param_mode	String	DISABLED	yes	SYSTEM imm.	N	Y		pdb replay parameter mode
_pdb_seed_mcsc	Boolean	FALSE	yes	SYSTEM imm.	N	Y		Allow PDB SEED to have different character set than the CDB.
_pdb_service_name_convert	String		yes	SYSTEM imm.	Y	Y		service name convert patterns and strings for per PDB clone
_pdb_service_on_root_listener	Boolean	FALSE	yes	SYSTEM imm.	Y	Y		pdb services on CDB ROOT listeners
_pdb_skiplist_apply_callout	String		yes	SESSION	Y	Y		PL SQL Procedure name to import skiplist
_pdb_skiplist_redogen_callout	String		yes	SESSION	Y	Y		PL SQL Procedure name to export skiplist
_pdb_skiplist_rfsgen_callout	String		yes	SESSION	Y	Y		PL SQL Procedure name to export skiplist in rfs setup
_pdb_small_table_threshold	Integer	20	yes	STATIC	Y	N		lower threshold level of table size for direct reads in a pdb
_pdb_strict_plugin_compat	Boolean	FALSE	yes	SESSION	Y	Y		Pluggable database strict plugin compatibility
_pdb_switchover_lifespan_callout	String		yes	SESSION	Y	N		PL SQL Procedure name to upload pdb lifespan
_pdb_transition_clean_bg_delay	Integer	0	yes	SYSTEM imm.	N	Y		delay in GEN0 to transition PDB to clean state
_pdb_trigger_user	String		yes	SESSION	Y	Y		user to execute pdb trigger
_pdb_use_sequence_cache	Boolean	TRUE	yes	STATIC	N	N		Use sequence cache in PDB mode
_pdb_vm_max_size	Big integer		yes	STATIC	N	N		PDB SGA maximum virtual memory size
_pdbopen_fixedtablestats	Boolean	FALSE	yes	STATIC	Y	N		gather fixed table stats at PDB open