DB_KEY | 
NUMBER | 
The primary key for the target database. Use this column to join with almost any other catalog view. | 
DBINC_KEY | 
NUMBER | 
The primary key for the incarnation of the target database. Use this column to join with RC_DATABASE_INCARNATION. | 
DB_NAME | 
VARCHAR2(8) | 
The DB_NAME of the database incarnation to which this record belongs. | 
RECID | 
NUMBER | 
The redo log history RECID from V$LOG_HISTORY. RECID and STAMP form a concatenated primary key that uniquely identifies this record in the target database control file. | 
STAMP | 
NUMBER | 
The redo log history stamp from V$LOG_HISTORY. RECID and STAMP form a concatenated primary key that uniquely identifies this record in the target database control file. | 
THREAD# | 
NUMBER | 
The thread number of the online redo log. | 
SEQUENCE# | 
NUMBER | 
The log sequence number of the redo log. | 
FIRST_CHANGE# | 
NUMBER | 
The SCN generated when switching into the redo log. | 
FIRST_TIME | 
DATE | 
The time stamp when switching into the redo log. | 
NEXT_CHANGE# | 
NUMBER | 
The first SCN of the next redo log in the thread. | 
CLEARED | 
VARCHAR2(3) | 
YES if the redo log was cleared with the ALTER DATABASE CLEAR LOGFILE statement; otherwise, NULL. This statement allows a log to be dropped without archiving it first. |