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Parent topic: Migrating SAP MBOs to OData Services

Previous: Create, Update, and Delete Entities

Delta Query Support for OData Services Exposed in NetWeaver Gateway

Convert MBO-based delta-tracking mechanisms to OData service delta-tracking mechanisms.

Comparing SAP Mobile Platform Version 2.x and 3.x Delta Tracking

  • SAP Mobile Platform 2.<x> uses replication-based synchronization between a client-side database and server-side cache database (CDB) to provide data communication between mobile applications and back-end systems. The CDB tracks deltas between back-end systems and the clients. To track changes:
    • SAP Mobile Platform Server must query the back end for all data, and check each row for changes, for example, by using a Scheduled or On-Demand cache group policy, or,
    • The back-end system must post changes as they occur to the CDB, for example, by using data change notification (DCN). This option is more efficient, because it does not require each row of data to be checked for changes.
  • SAP Mobile Platform 3.<x> delta tracking is managed by the back-end system. OData services can use delta queries and delta tokens to mimic 2.<x> CDB delta-tracking capabilities.
See Delta Query Support for more information.

In this section:
    Understanding Delta Query Support
    A delta query requests all entities that have been created, changed, or deleted since the prior query. The delta query protocol defines a pull-model protocol for clients to obtain changes in entity sets.
    Implementing Delta Queries
    There are several methods you can use to implement delta query support. Two of them involve using Syclo Exchange Framework exchange tables, and using ABAP-based delta request logs.

Parent topic: Migrating SAP MBOs to OData Services

Previous: Create, Update, and Delete Entities