Data Change Notification's Effect on the SAP Mobile Server Cache

Supported DCN types and their effect on the SAP Mobile Server cache (CDB):

DCN with operation replay (without payload) – as an example, the EIS contains information for the Customer MBO, with an EIS primary key cust_id, and the MBO model includes a READ operation that retrieves all Customer details and populates the CDB using cust_id. In DCN without payload, if the EIS notices that customer data for cust_id=123 has changed in the EIS, it can send a DCN to SAP Mobile Server with essentially:
```
{MBO=customer, operation=read, cust_id=123}
```
to inform SAP Mobile Server to execute the read operation that updates the CDB with cust_id=123 changes. This form of DCN involves a lot of interactions with SAP Mobile Server and the EIS to pull data changes into the CDB.
DCN with payload – is more efficient since the EIS sends a DCN containing the data:
```
{MBO=customer, operation=upsert, {cust_id=123, fname=John, lname=Smith, address=...}}
```
when the EIS notices that cust_id=123 has changes, and SAP Mobile Server applies these changes directly to the CDB without additional calls to the EIS.
Hybrid App DCN – used to push notifications triggered by the EIS to the Hybrid App and has nothing to do with the CDB.