Maybe you can create fields of type function in an object which will act like a proxy for the other database/external application you have. Just make sure your external database/app is accessible using Python. But this approach would make the fields read only.

If you want to allow changes to be made from OpenERP: Create object with stored fields (not function fields) which mirrors the external database field.

• Override 'read' method to populate the mirroring fields by reading values from the external database.
• Override 'write' method to allow changes from OpenERP frontend to be made to external database.

e.g:

def read(self, cr, uid, ids, fields=None, context=None):
    #Populate local fields with values from external database
    res = super(your_proxy_object, self).read(cr, uid, select, fields=fields, context=context)
    return res

def write(self, cr, uid, ids, vals, context=None):
    #Write changes to external database
    return super(your_proxy_object, self).write(cr, uid, ids, vals, context=context)

There is a simple module to access data in foreign databases from OpenERP: base_external_dbsource in branch lp:openobject-extension. I have used it toaccess data from Oracle an SQL Server databases. It should be difficult to extend it to also add write features.

You can find more about in it's manifest.

Hello For testing I installed the module base_external_dbsource and created an externel data source. Connection to my external db is successful, but now I dont know how to use this connection in my custom module. Are there any informations how to use this connection and make the external data available in a module ? Can someone help? René