Database query performance

In the previous section, we saw how IEnumerator is different from and performs faster than IEnumerable when iterating through an in-memory collection. Now, let's query a database and iterate through the resulting collection using various benchmarked techniques. To do so, we'll follow these steps:

1. Add a new class called IEnumeratorVsIQueryable.
2. We will be connecting to a SQL Server database, and we will have information we need to keep secret. Our secret.json files do not get checked into version control. So, right-click on the project and select Manage User Secrets from the context menu.
3. A dialog box will pop up, informing you that additional packages are required. Click on Yes:

Figure 6.6 – A dialog box, informing you that additional packages are required to manage user secrets

4. Visual Studio will then open the secrets.json file in a new tab. This is where you will add your user secrets.
...