Which four are true about RMAN backup sets? (Choose four.)
Which four are true about RMAN backup sets? (Choose four.)
A backup piece can belong to only one backup set since each backup set is a distinct collection of backup pieces. RMAN can create a multisection backup, where a single backup set can contain multiple sections of a single data file, stored in different backup pieces within the same backup set. Blocks from multiple data files can be contained in one backup piece, allowing more efficient use of storage. Finally, blocks from multiple data files can be contained in one backup set, enabling RMAN to back up several data files into a single backup set.
ACDH A backup set contains one or more binary files in an RMAN-specific format. Each of these files is known as a backup piece. So E is Wrong.
Backup sets are produced by the RMAN BACKUP command. A backup set usually consists of only one backup piece. RMAN divides the contents of a backup set among multiple backup pieces only if you limit the backup piece size using the MAXPIECESIZE option of the ALLOCATE CHANNEL or CONFIGURE CHANNEL command. https://docs.oracle.com/cd/E18283_01/backup.112/e10642/glossary.htm#i432144
ACDH A backup set contains one or more binary files in an RMAN-specific format. Each of these files is known as a backup piece. A backup set can contain multiple datafiles. For example, you can back up 10 datafiles into a single backup set consisting of a single backup piece.
A -wrong must not can
D is true, a backup set can contain multiple datafiles. For example, you can back up 10 datafiles into a single backup set consisting of a single backup piece.
My opinion: A: Wrong because a backup piece must be belong to only one backup set C: Backup with SECTION SIZE D: Backup with FILESPERSET > 1 when MAXPIECESIZE is unlimited E: Backup Only One Datafile (Small) for SET FILESPERSET=1 H: Backup with FILESPERSET > 1 and limit the MAXPIECESIZE
A, C ,D, H - tested in practice minutes ago.
A, C, D, H
CDEH A backup set contains one or more binary files in an RMAN-specific format. Each of these files is known as a backup piece. A backup set can contain multiple datafiles. For example, you can back up 10 datafiles into a single backup set consisting of a single backup piece. In this case, RMAN creates one backup piece as output. The backup set contains only this backup piece. If you specify the SECTION SIZE parameter on the BACKUP command, then RMAN produces a multisection backup. This is a backup of a single large file, produced by multiple channels in parallel, each of which produces one backup piece. Each backup piece contains one file section of the file being backed up.
I believe, that option E is wrong. It use colocation "can only" which I consider as a "must". So backup set can, but not must, contain 1 backup piece.
"Backup set contains ONE or more binary files... known as backup piece", then, a Backup set CAN contain only ONE backup piece (E True). Blocks from multiple data files can be contained in one backup set, but not in the SAME backup piece (D False). Then, ACEH (i think...)
Sorry, my previous answer is wrong. ACDH is my definitive bet
I believe it's ACDH.
according to this guy A seems correct https://rajat1205sharma.wordpress.com/2015/07/03/rman-basics/
ACDE , A. "can" "only one" sounds enough restrictive to me C. multisection backup D. D and H are similar questions, but H is more accurate answer E. "A backup set contains one or more binary files in an RMAN-specific format.Each of these files is known as a backup piece." https://docs.oracle.com/en/database/oracle/oracle-database/19/bradv/rman-backup-concepts.html#GUID-1C871377-D8A7-4414-B0F0-884403666E8C
Correction D. D and H are similar questions, but D is more accurate answer
answer is ACEH D is incorrect
I believe alternative D is wrong due to the term "blocks of multiple datafiles". A backup set can contain multiple data files. For example, you can back up 10 data files into a single backup set consisting of a single backup piece. In this case, RMAN creates one backup piece as output. The backup set contains only this backup piece. If you specify the SECTION SIZE parameter on the BACKUP command, then RMAN produces a multisection backup. This is a backup of a single large file, produced by multiple channels in parallel, each of which produces one backup piece. Each backup piece contains one file section of the file being backed up.
A -- backup set consists of backup pieces. B -- wrong, C -- multisection backup. D -- wrong, E -- It CAN. F,G -- wrong, a backup set may be written to media or to disk, H -- sure, as the backup set can contain multiple datafiles.
A is wrong : not can but must
sorry ACDH, I misinterpreted the sentence
I have no idea, I'm in doubt... but, my kick is A,C,D,H
A: I perceive "must" as equal to "can only", even in my native language. C: One backup piece can contain multiple data files or parts of split data files, but all such backup pieces belong to the same backup set, and by extension, the split data file also belongs to one backup set. D: One backup piece can contain multiple (blocks from) data files. H: By extension of D, (blocks from) multiple data files can be contained in one backup set.
A. TRUE: A backup set contains one or more binary files in an RMAN-specific format. Each of these files is known as a backup piece. B. False : When creating backup sets, RMAN can simultaneously read multiple files from disk and then write their blocks into the same backup set. C. TRUE: RMAN can create a multisection backup. In this case, a single backup set can contain multiple backup pieces D. TRUE : For example, RMAN can read from two data files simultaneously, and then combine the blocks from these data files into a single backup piece. E. FALSE : A backup set contains one or more binary files in an RMAN-specific format. Each of these files is known as a backup piece. F. FALSE : CAN not MUST G. FALSE : CAN not MUST H. TRUE: When creating backup sets, RMAN can simultaneously read multiple files from disk and then write their blocks into the same backup set.
Source: https://docs.oracle.com/en/database/oracle/oracle-database/23/bradv/rman-backup-concepts.html#GUID-74FF41AF-D1EE-4DB1-AC0D-56FC83CAA91D