Implementing the CQRS design pattern

In this section, we will look at the Command Query Responsibility Separation (CQRS) design pattern. In simple terms, a command is a method that performs an action, while a query is a method that returns data. Commands do not perform queries, and queries do not perform commands. Commands can have separate models for queries. Now, let’s write a simple console application that demonstrates how easy it is to implement this pattern, which is used extensively in microservice development:

1. Start a new console application called CH13_CQRSPattern.
2. Add a new class called CQRSBasedClass.
3. Add the SleepCommand method:

   public void SleepCommand(int milliseconds)
   {
       Thread.Sleep(milliseconds);
   }

Our SleepCommand method is an example of a command. It takes in a parameter that is several milliseconds in length. A command is then executed that causes the current thread to sleep for the number of milliseconds specified...