This page describes the upgrade path from Datastore to Firestore.
Firestore can operate in Datastore mode, making it backwards- compatible with Datastore. By creating a Firestore database in Datastore mode, you can access Firestore's improved storage layer while keeping Datastore system behavior. Firestore in Datastore mode removes the following Datastore limitations:
- Queries are no longer eventually consistent; instead, they are all strongly consistent.
- Queries in transactions are no longer required to be ancestor queries.
- Transactions are no longer limited to 25 entity groups.
- Writes to an entity group are no longer limited to 1 per second.
- Transactions now use pessimistic locks instead of optimistic concurrency
For more about Datastore mode, see Firestore in Datastore mode.
Starting in 2021, Google Cloud will gradually upgrade existing Datastore databases to Firestore in Datastore mode.
Automatic upgrade to Cloud Firestore in Datastore mode
When the automatic upgrade process begins in 2021, Google Cloud will begin contacting owners of existing Datastore databases to schedule an automatic upgrade to Firestore in Datastore mode.
If you manage an application that uses Datastore, you will not need to update your application code. We will notify you about the schedule of your application's upgrade to Datastore Mode. The upgrade will not require downtime.
For additional questions about the automatic upgrade process, contact one of our support channels.
Testing an existing application
For an existing app that uses Datastore, you can test app behavior with Firestore in Datastore mode by doing the following:
- Create a new project. In this project, create a Firestore in Datastore mode database.
- Using the managed export service, export some of your application's data to Cloud Storage.
- Using the managed import service, import your application's data to your new project.
- Copy app logic you want to test to the new project or simulate app behaviour against the new project.