[Developers] Incremental download

[John Giannandrea]

Sumit wrote:
> Btw, will the timestamp condition apply to only new records i.e.  
> topics applied after the given timestamp, OR to records that were  
> updated after the timestamp as well?

If you want to track all the changes to one or more objects after a  
specific timestamp, you will need to query for additions, deletions  
and updates i.e. pay attention to the operation property of /type/link

The history mechanism is documented in chapter 3 of the MQL manual:   http://mql.freebaseapps.com/ch03.html#history

-jg