DataBase Handle
Holds state regarding position in the database
| DataBaseHandle () | DataBaseHandle | 
| DataBaseHandle (bool v, uint32_t last_entry, OspfTypes::PeerID peerid) | DataBaseHandle | 
| uint32_t  position () | position | 
[const]
| uint32_t  last () | last | 
[const]
| void  advance (bool& last) | advance | 
| bool  valid () | valid | 
[const]
| void  invalidate () | invalidate | 
| OspfTypes::PeerID  get_peerid () | get_peerid | 
[const]