6.17 DBA_HIST_PARAMETER

DBA_HIST_PARAMETER displays historical information about the initialization parameters that were in effect for the instance.

This view contains snapshots of V$SYSTEM_PARAMETER.

Column Datatype NULL Description

SNAP_ID

NUMBER

NOT NULL

Unique snapshot ID

DBID

NUMBER

NOT NULL

Database ID for the snapshot

INSTANCE_NUMBER

NUMBER

NOT NULL

Instance number for the snapshot

PARAMETER_HASH

NUMBER

NOT NULL

Parameter hash

PARAMETER_NAME

VARCHAR2(64)

NOT NULL

Name of the parameter

VALUE

VARCHAR2(512)

Parameter value for the session (if modified within the session); otherwise, the instance-wide parameter value

ISDEFAULT

VARCHAR2(9)

Indicates whether the parameter is set to the default value (TRUE) or the parameter value was specified in the parameter file (FALSE)

ISMODIFIED

VARCHAR2(10)

Indicates whether the parameter has been modified after instance startup:

  • MODIFIED - Parameter has been modified with ALTER SESSION

  • SYSTEM_MOD - Parameter has been modified with ALTER SYSTEM (which causes all the currently logged in sessions' values to be modified)

  • FALSE - Parameter has not been modified after instance startup

CON_DBID

NUMBER

The database ID of the PDB for the sampled session

CON_ID

NUMBER

The ID of the container that CON_DBID identifies. Possible values include:

  • 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs.

  • 1: This value is used for rows containing data that pertain to only the root

  • n: Where n is the applicable container ID for the rows containing data

See Also:

"V$SYSTEM_PARAMETER"