I need to replicate certain sets of data from a master database site (head office) to multiple sites geographically distributed.
There is no specific software chosen for head office or the remote sites.
The remote sites should be able to make data changes and these changes should be synced to head office and the other way around.
Very poor connectivity between H/O and some remote sites.
The remote sites should contain only sub sets of data from the master and some sites will need to have different sets than other sites.
And finally there is approximately 5000 remote sites.
Currently testing on postgres at the remote sites and using database links with materialized views to retrieve data from head office.
Tested the head office system with oracle and postgresql.
Because of the poor connectivity between the H/O and certain sites, I would like to only retrieved changed data when I refresh the data on the sites.
I know oracle uses the materialized view log to track changed data for fast refreshes.
Any information would be greatly appreciated.