Backup Concepts in Reorganizations 
SAPDBA does not perform an automatic backup before or after a reorganization. Depending on the reorganization type, however, SAP highly recommends backing up the relevant data. Please follow the following recommendations:
Reorganization of a Single Object/List of Objects
Before
a table/index reorganization, you should always back up the data in the table(s), for example, using the SAPDBA option Export/import. In case of error, repeat the reorganization operation, for example, by using the restart functionality. If this attempt also fails, use the backup of the data to restore the old status and repeat the reorganization. Pay special attention to the sequence of the actions that you perform. The actions listed above in case of error should be performed immediately, to guarantee consistency of the database.Reorganization of a Tablespace (Without Data Files)
Before
a tablespace reorganization without data files, you should make a complete backup of the database (online possible; offline recommended). To do this, use the BRBACKUP utility program, which you can start manually or with the SAPDBA option Backup database. When the last complete backup of the database was not performed too long ago, and all redo log files up to the point when the reorganization is started are complete and available (on disk, when possible), you do not have to back up the database again. In this case, the database could be restored from the last available backup, should this prove necessary.After a successful reorganization, you should back up at least the relevant tablespaces, since the reorganization process is very time-intensive.
Reorganization of a Tablespace with Data Files
Before
a tablespace reorganization with data files, you should make a complete backup of the database (online possible; offline recommended). To do this, use the BRBACKUP utility, which you can start with the SAPDBA option Backup database. When the last complete backup of the database was not performed too long ago, and all redo log files up to the point when the reorganization is started are complete and available (on disk, when possible), you do not have to back up the database again. In this case, the database could be restored from the last available backup, should this prove necessary.After a tablespace reorganization with data files, you must at least back up the relevant tablespaces; any required recovery with SAPDBA is otherwise not possible after such structure changes. In this case, SAPDBA automatically displays the backup menu, to enable you to immediately start the backup of the relevant tablespaces.

A tablespace backup after reorganization is sufficient when you operate the database in ARCHIVELOG mode. If not, the required degree of security can only be achieved by backing up the entire database. If a large number of tablespaces require reorganization, we always recommend a complete offline backup of the database before reorganization of the first tablespace and after reorganization of the last tablespace.
Move/Rename Data Files of a Tablespace
After
moving or renaming the data files of a tablespace, you must perform at least a backup of the corresponding tablespace, since otherwise you cannot implement a recovery of the database with SAPDBA after such a change if there should be an error. In this case SAPDBA automatically displays the backup menu, so that you can immediately start the backup of the corresponding tablespace.