OS_USERNAME | 
VARCHAR2(255) | 
  | 
Operating system login username of the user whose actions were audited | 
USERNAME | 
VARCHAR2(30) | 
  | 
Name (not ID number) of the user whose actions were audited | 
USERHOST | 
VARCHAR2(128) | 
  | 
Client host machine name | 
TERMINAL | 
VARCHAR2(255) | 
  | 
Identifier of the user's terminal | 
TIMESTAMP | 
DATE | 
  | 
Date and time of the creation of the audit trail entry (date and time of user login for entries created by AUDIT SESSION) in the local database session time zone | 
ACTION_NAME | 
VARCHAR2(28) | 
  | 
Name of the action type corresponding to the numeric code in the ACTION column in DBA_AUDIT_TRAIL | 
LOGOFF_TIME | 
DATE | 
  | 
Date and time of user log off | 
LOGOFF_LREAD | 
NUMBER | 
  | 
Logical reads for the session | 
LOGOFF_PREAD | 
NUMBER | 
  | 
Physical reads for the session | 
LOGOFF_LWRITE | 
NUMBER | 
  | 
Logical writes for the session | 
LOGOFF_DLOCK | 
VARCHAR2(40) | 
  | 
Deadlocks detected during the session | 
SESSIONID | 
NUMBER | 
NOT NULL | 
Numeric ID for each Oracle session | 
RETURNCODE | 
NUMBER | 
NOT NULL | 
Oracle error code generated by the action. Some useful values:
 | 
CLIENT_ID | 
VARCHAR2(64) | 
  | 
Client identifier in each Oracle session | 
SESSION_CPU | 
NUMBER | 
  | 
Amount of CPU time used by each Oracle session | 
EXTENDED_TIMESTAMP | 
TIMESTAMP(6) WITH TIME ZONE | 
  | 
Timestamp of the creation of the audit trail entry (timestamp of user login for entries created by AUDIT SESSION) in UTC (Coordinated Universal Time) time zone | 
PROXY_SESSIONID | 
NUMBER | 
  | 
Proxy session serial number, if an enterprise user has logged in through the proxy mechanism | 
GLOBAL_UID | 
VARCHAR2(32) | 
  | 
Global user identifier for the user, if the user has logged in as an enterprise user | 
INSTANCE_NUMBER | 
NUMBER | 
  | 
Instance number as specified by the INSTANCE_NUMBER initialization parameter | 
OS_PROCESS | 
VARCHAR2(16) | 
  | 
Operating System process identifier of the Oracle process |