This page hosts the detailed specification for the [https://blueprints.launchpad.net/sahana3/+spec/synchronisation Blueprint for the Synchronisation].

We need to be able to support synchronising data between instances:
 * http://wiki.sahana.lk/doku.php?id=doc:sync:english

In S2 this is done by record ids being UUIDs (Universally Unique IDs) built from each instance's 'base_uuid'

There is a sync_instance table:
{{{
CREATE TABLE sync_instance (
    base_uuid VARCHAR(4) NOT NULL, -- Instance id
    owner VARCHAR(100), -- Instance owner's name
    contact TEXT, -- Contact details of the instance owner
    url VARCHAR(100) DEFAULT NULL, -- Server url if exists
    last_update TIMESTAMP NOT NULL, -- Last Time sync with the instance
    sync_count INT DEFAULT 0, -- Number of times synchronized
    PRIMARY KEY(base_uuid)
);
}}}


Web2Py users have tried to solve the same issue:
 * http://groups.google.com/group/web2py/browse_thread/thread/af3f7ad5271a10c6/c5e96141c13a29ad

Inc through UUIDs:
 * http://groups.google.com/group/web2py/browse_thread/thread/7d639c98b5b8dcd2/c0fe17ccbdd12eb7

{{{
import uuid
SQLField('uuid',default=str(uuid.uuid4())) 
}}}

There is a simple 1-table example appliance which has the ability to do syncs via XML-RPC:
 * http://mdp.cti.depaul.edu/appliances/default/download/app.source.312926207134.txt

We can use CSV to do database synchronization:
 * http://groups.google.com/group/web2py/browse_thread/thread/be927ccf4d9745d2/637e45ccc2cf2583
 * http://groups.google.com/group/web2py/browse_thread/thread/55d923a51eca2c90