Programming Google App Engine with Java

Chapter 9. Datastore Administration

Your data is the heart of your application, so you’ll want to take good care of it. You’ll want to watch it, and understand how it grows and how it affects your app’s behavior. You’ll want to help it evolve as your app’s functionality changes. You may even want up-to-date information about data types and sizes. And you’ll want to poke at it, and prod it into shape using tools not necessarily built into your app.

App Engine provides a variety of administrative tools for learning about, testing, protecting, and fixing your datastore data. In this chapter, we look at a few of these tools, and their associated best practices.

Inspecting the Datastore

The first thing you might want to do with your app’s datastore is see what’s in it. Your app provides a natural barrier between you and how your data is stored physically in the datastore, so many data troubleshooting sessions start with pulling back the covers and seeing what’s there.

In the Storage section of the Cloud Console is a set of panels for Cloud Datastore (Figure 9-1). This is your main view of your project’s datastore entities. The Dashboard summarizes how your storage space is used, including space for entities and their properties, as well as space for built-in and custom (composite) indexes. Select a kind from the drop-down menu to see a breakdown by named property.

In the Query panel, you can browse entities by kind. You can also apply query filters to this view by clicking the Filters ...