You perform differential incremental level 1 backups of your database on each working day
and level 0 backup on Sunday to tape: Which two statements are true about differential
incremental backups? (Choose two.)
A.
The backup performed on Sundays contains all the blocks that have ever been used in
the database
B.
The backup performed on Monday contains all the blocks that have changed since the
level 0 backup and every other working day contains all the blocks that have changed since
the level 1 backup
C.
The backup performed on each working day contains all the blocks that have changed
since the last level 0 backup
D.
The backup performed on Sundays contains all the blocks that have changed since the
last level 1 backup
A and B are the best answers here.
However the problem with A is that it is possible to create a table and insert some data and then DROP it with a PURGE. Then when you take a backup the blocks that were used by this table are not in the level 0 backup. So you cannot say “all the blocks that have ever been used in the database”.
Better to say
“all the blocks that are in use in the database”
The problem with B is that you cant say
“all the blocks that have changed since the level 1 backup”
because this is ambigious, which level 1 backup? It would be better to say
“all the blocks that have changed since the last level 1 backup”
Peace to all