Appboard/old/advanced data adapter

Prerequisites

These examples use the same system configuration as the Creating An AppBoard Data Adapter examples. Review the required environment and verify it using the steps on that page before continuing.

Advanced Data Adapter Concepts

The previous examples demonstrate how to develop the necessary callback methods for the AppBoard system to interrogate an adapter for its Entities and related settings. It also demonstrated the use of fetchRecords() to retrieve all the content for a given Entity. While this approach is sufficient for many adapters, the advanced topics in this walkthrough will illustrate how to be more efficient in memory and network bandwidth usage through the use of other methods to retrieve the data.

These examples will demonstrate the following concepts:

1. Partial record retrieval -- Instead of retrieving all the attributes for each record, the adapter can return only some of the attributes, and when needed, the client will request the remainder
2. Custom query implementation -- Default query mechanism relies on the server having all records for an entity. If the adapter's data source permits filtered retrieval, the adapter can intercept incoming queries and handle them more efficiently.
3. (Future) More discrete cache control

Refactoring fetchRecords()

As a