docs: Add details about `schema::Database`.
=========
Databases
=========
+
+An EdgeDB cluster can have multiple databases in it. The
+:eql:stmt:`CREATE DATABASE` EdgeQL command adds a new database to the
+EdgeDB cluster.
+
+The following command will get a list of all databases present in the
+cluster:
+
+.. code-block:: edgeql
+
+ SELECT schema::Database.name;
