Oracle RMAN Number of Days Since Last Backup

Question:  How can I see the number of days since my last backup? 

It is easy to see the number of days since the last backup in MSSQL, but I need to know how to see the backup frequency in Oracle.

Answer:  There are many ways to see the number of days since your last Oracle backup. 

Unlike MS-SQL, Oracle provides many backup methods:

• RMAN

•  OS backups

•  3rd party backup tools (Symantec, Veritas, Omniback etc.)

If you are using RMAN for your backups, there is a catalog database you can query with as set of RMAN commands:

RMAN> list archivelog all backed up 1 times to device type xxx;

You can see the frequency and dates of backups using the RMAN catalog tables:

•  rc_backupset_summary

• rc_backup_set

Or query the v$ views for RMAN backup completion details:

• v$rman_status

•  v$backup_set

These RMAN SQL queries will all find the number of days since the last database backup:

 -- *****************************************
-- SQL for v$backup_set to see last backup
-- *****************************************

select *
    from
    v$backup_set
where
    completion_time > sysdate-7
order by
    completion_time desc;

-- *****************************************
-- SQL for rc_backup_set to see most recent backup
-- *****************************************

select *
from
    rc_backup_set
where
    completion_time > sysdate-7
order by
    completion_time desc;

-- *****************************************
-- Display most recently completed RMAN backup
-- *****************************************

select *
from
    rc_backup_set
where
    backup_type = 'D'
and
    controlfile_included = 'BACKUP'
order by
    completion_time desc

-- *****************************************
-- Display newest_backupset_time for RMAN backup
-- *****************************************

select
    db_name,
    newest_backup_time
from
    rman.rc_backupset_summary  
where
    dn_name = 'MKYSID';

-- *****************************************
-- You can also outer join rc_backupset_summary
-- into rc_database to see the RMAN latest backup start time:
-- *****************************************

select
    name,
    max(start_time)
from
    rman.rc_database     d,
    rman.rc_backup_set  s
where
    db_id(+) = dbid
group by
    name
order by 2 desc;

-- *****************************************
-- Display RMAN backupo status start and end times:
-- *****************************************

select
    operation,
    status,
    object_type,
    to_char(start_time,'mm/dd/yyyy:hh:mi:ss') as start_time,
    to_char(end_time,'mm/dd/yyyy:hh:mi:ss') as end_time
from
    v$rman_status
where
    start_time > SYSDATE -1
and
    operation = 'BACKUP'
and
    object_type = 'DB FULL'
order by
    start_time desc;

There are many more permutations of RMAN queries to see the latest backup details, see the Oracle RMAN book for details.

Get the Complete Oracle SQL Tuning Information  The landmark book "Advanced Oracle SQL Tuning  The Definitive Reference"  is filled with valuable information on Oracle SQL Tuning. This book includes scripts and tools to hypercharge Oracle 11g performance and you can buy it for 30% off directly from the publisher.