Adding Username for Database Connections
For database connections, you can have your users sign in with a username instead of their email address.
To add a required username:
Go to the Connections -> Database section of the dashboard.
Select the connection you wish to edit by clicking on the connection name or the Settings gear icon.
Under Settings, you will see Requires Username, use the toggle here to enable/disable requiring a username.
You can see how the this will affect the login screen by clicking on Try Connection. You can see that once Requires Username is enabled, new users will have to enter a username and their email address to sign up.
Users can then login with either their username or their email address. For users who registered while Requires Username was disabled, there will be no Username field stored for them and they will have to login with their email.
Username length limitations
The default allowed length for usernames is between 1 and 15 characters. However, using the dashboard or via API v2, you can modify the length minimum and maximum (up to a maximum length of 128 characters).