Multi-database is a new feature that allows you to create multiple database instances.
To get started, you need to be in the Blaze plan. In the data viewer, you can click the triple point icon to create new database instances:

To access data from a secondary instance, you use an absolute URL when creating the database instance.
const app = firebase.initializeApp({ // use your main config databaseUrl: "https://multi-db.firebaseio.com/" }); const db1 = app.database(); // This is the default DB const db2 = app.database("https://multi-db501c7.firebaseio.com/");
Because these databases are in the same project, they use the same authentication session.
Each database instance also has its own set of security rules, and databases can handle different structures.
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