One or multiple data sources for multiple influx db databases?

I’m running one influxdb server but have multiple databases.

Is it best practice to setup multiple data sources in Grafana (i.e. one data source for each influxdb database) or only one data source?

When adding a data source to Grafana, it shows the following:

Database Access

Setting the database for this datasource does not deny access to other databases. The InfluxDB query syntax allows switching the database in the query. For example: SHOW MEASUREMENTS ON _internal or SELECT * FROM “_internal”…“database” LIMIT 10

…but when I try to use the Explore in Grafana to see my other databases I can’t seem to figure it out?

I use one datasource for each database, and I use around 20 of them. Although you can manually set the database on a query’s FROM, you then need to switch to the manual query editor and skip the builder. I prefer to just set the the datasource to define the database, and to create queries using the builder as much as possible, to keep them more editable and readable.

In fact, I don’t think you can define an InfluxDB datasource without setting a database?