Tivoli Data Protection for Lotus Domino provides two types of database
backup—incremental and selective—and a log archive function. Incremental
backup provides a conditional backup function that creates a full on-line
backup of Domino databases, when necessary. The specific conditions that
determine when a new backup is necessary vary depending on whether the
database is logged or not. Selective backup unconditionally backs up the
specified databases, unless they are excluded from backup through exclude
statements. When archival logging is in effect, changes to logged databases
can be captured in between full backups, by archiving the transaction log.

let me change my Q ,Does selective backup is brick level 
(brick level backup - most common with MS Exchange ,backup/restore of one
inbox and not all the DB)