Description of formatspec.gif follows
Description of the illustration formatspec.gif


To specify a filename format or an Automatic Storage Management disk group for a backup piece or image copy. If you do not specify a value for the FORMAT parameter, then RMAN either creates the backup in the flash recovery area if it is enabled, or in a port-specific directory (for example, ?/dbs on UNIX) if a flash recovery area is not enabled. In either case, RMAN uses the variable %U to name the backup.

The entire format_string is processed in a port-specific manner by the target instance to derive the final backup piece name. The substitution variables listed in "Keywords and Parameters" are available in FORMAT strings to aid in generating unique filenames. The formatting of this information varies by platform.

Order of Precedence for Multiple Format Strings

You can specify up to four FORMAT strings. RMAN uses the second, third, and fourth values only when BACKUP COPIES, SET BACKUP COPIES, or CONFIGURE ... BACKUP COPIES is in effect. When choosing the format for each backup piece, RMAN uses the first format value for copy 1, the second format value for copy 2, and so on. If the number of format values exceeds the number of copies, then the extra formats are not used. If the number of format values is less than the number of copies, then RMAN reuses the format values, starting with the first one.

Specify format_string in any of these places, listed in order of precedence:

  1. The backupSpec clause

  2. The BACKUP command

  3. The ALLOCATE CHANNEL command

  4. The CONFIGURE CHANNEL command

If specified in more than one of these places, then RMAN searches for the FORMAT parameter in the order shown.

Restrictions and Usage Notes

Any name that is legal as a sequential filename on the platform is allowed, so long as each backup piece or copy has a unique name. If backing up to disk, then any legal disk filename is allowed, provided it is unique.

Keywords and Parameters

Syntax Element Description
%a Specifies the activation ID of the database.
%c Specifies the copy number of the backup piece within a set of duplexed backup pieces. If you did not duplex a backup, then this variable is 1 for backup sets and 0 for proxy copies. If one of these commands is enabled, then the variable shows the copy number. The maximum value for %c is 256.
%d Specifies the name of the database.
%D Specifies the current day of the month from the Gregorian calendar in format DD.
%e Specifies the archived log sequence number.
%f Specifies the absolute file number.
%F Combines the DBID, day, month, year, and sequence into a unique and repeatable generated name. This variable translates into c-IIIIIIIIII-YYYYMMDD-QQ, where:
  • IIIIIIIIII stands for the DBID. The DBID is printed in decimal so that it can be easily associated with the target database.

  • YYYYMMDD is a time stamp in the Gregorian calendar of the day the backup is generated

  • QQ is the sequence in hexadecimal number that starts with 00 and has a maximum of 'FF' (256)

%h Specifies the archived redo log thread number.
%I Specifies the DBID.
%M Specifies the month in the Gregorian calendar in format MM.
%N Specifies the tablespace name.
%n Specifies the name of the database, padded on the right with x characters to a total length of eight characters. For example, if the prod1 is the database name, then the padded name is prod1xxx.
%p Specifies the piece number within the backup set. This value starts at 1 for each backup set and is incremented by 1 as each backup piece is created.

Note: If you specify PROXY, then the %p variable must be included in the FORMAT string either explicitly or implicitly within %U.

%s Specifies the backup set number. This number is a counter in the control file that is incremented for each backup set. The counter value starts at 1 and is unique for the lifetime of the control file. If you restore a backup control file, then duplicate values can result. Also, CREATE CONTROLFILE initializes the counter back to 1.
%t Specifies the backup set time stamp, which is a 4-byte value derived as the number of seconds elapsed since a fixed reference time. The combination of %s and %t can be used to form a unique name for the backup set.
%T Specifies the year, month, and day in the Gregorian calendar in this format: YYYYMMDD.
%u Specifies an 8-character name constituted by compressed representations of the backup set or image copy number and the time the backup set or image copy was created.
%U Specifies a system-generated unique filename (default). The meaning of %U is different for image copies and backup pieces.

For a backup piece, %U specifies a convenient shorthand for %u_%p_%c that guarantees uniqueness in generated backup filenames. If you do not specify a format when making a backup, then RMAN uses %U by default.

For an image copy of a datafile, %U means the following:


For an image copy of an archived redo velog, %U means the following:


For an image copy of a control file, %U means the following:


%Y Specifies the year in this format: YYYY.
%% Specifies the literal '%' character. For example, %%Y translates to the string %Y.


Specifying an ASM Disk Group: Example This example copies the database to ASM disk group disk1:


Specifying a Format for Datafile Copies: Example This example creates copies of three datafiles with tag 'LATESTCOPY' to directory /copies:

# Create copies of 3 datafiles with tag 'LATESTCOPY' to directory /copies
  COPY OF DATAFILE 4, 6, 14 
  FORMAT '/copies/Datafile%f_Database%d';

Creating a Database Copy for Use as a Standby Database: Example This example creates an image copy of the database to instantiate a physical standby in /stby:

# Create an image copy of the database to instantiate physical standby in /stby 
  FORMAT '/stby/standby_file_%f_of_db_%I';