6853 Too many partition ranges qualified
The user is trying to perform a backup or restore operation with a PARTITIONS WHERE clause that results in too many distinct partition ranges to scan. This might occur if your WHERE clause enumerated distinct partition values such as "WHERE PARTITION IN (1,3,5,etc.)" instead of using a range of values such as with "WHERE PARTITION BETWEEN 1 AND 1000". The former expression results in every odd number being a distinct partition range whereas the latter is only a single partition range. Up to 100 distinct partition ranges are supported.
Simplify the PARTITIONS WHERE clause and re-submit the job.