A Phoenix.LiveDashboard.PageBuilder page exposing EctoCockroachExtras stats.

Phoenix.LiveDashboard's built-in Ecto Stats page dispatches by repo.__adapter__() (Ecto.Adapters.Postgres -> EctoPSQLExtras, etc.), and a CockroachDB repo also reports Ecto.Adapters.Postgres (it uses Ecto's Postgres adapter over the wire protocol), so it would be wrongly routed to EctoPSQLExtras. Use this page instead, wired in explicitly:

live_dashboard "/dashboard",
  additional_pages: [
    cockroach_stats: {EctoCockroachExtras.LiveDashboardPage, repos: [MyApp.Repo]}
  ]

Note: unlike the built-in Ecto Stats page, this page always queries the given repo(s) from the local node - it does not support fetching stats for repos running on a different clustered BEAM node.