Data and data access technologies

We did an overview of the characteristics and requirements of different layers of distributed applications. Now we will go through the most crucial layer of any distributed application, the data layer. In this part, you will be introduced to various database technologies, along with .NET-related technologies.

Data can be stored in a wide range of data sources such as relational databases, files on the local filesystems, on the distributed filesystems, in a caching system, in storage located on the cloud, and in memory.

• Relational databases (SQL server): This is the traditional data source that is designed to store and retrieve data. Queries are written in languages such as T-SQL-utilized Create, Retrieve, Update, and Delete (CRUD) operations model. We will have an overview of the SQL server and its use with Entity Framework in this chapter.
• The filesystem: The filesystem is used to store and retrieve unstructured data on the local disk system in the files...