Almost all applications and services need to store and access some kind of data. For example, the retail application discussed in this guide needs to store product, customer, and order data.
When working with data, you need to determine:
The data store you are using.
The design of the components used to access the data store.
The format of the data passed between components, and the programming model it requires.
Your application or service may have one or more data sources, and these data sources may be of different types. The logic used to access data in a data source will be encapsulated in data access logic components, which provide methods for querying and updating data. The data your application logic needs to work is related ...