Database changes | nostrbase docs

const channel = db
  .channel("pending-todos")
  .on("nostr_changes", {
    table: "todos",
    event: "*",
    author: pubkey,
    filter: "done=eq.false",
  }, ({ eventType, new: next, old: previous }) => {
    console.log(eventType, next, previous);
  })
  .subscribe((status, error) => {
    if (error) console.error(status, error);
  });

await db.removeChannel(channel);

postgres_changes is an alias for the same event type. Payloads contain INSERT, UPDATE, or DELETE, the new and old rows, and the signed event. Initial cached or relay records arrive as INSERT. Duplicate and stale versions are ignored. For filtered updates, a callback runs when either the old or new row matches. This lets an app remove a row that leaves its filter.

SUBSCRIBED means local handlers are installed. It is not a relay readiness or replay-completion signal. Reconnects use Applesauce’s retry policy. A terminal relay error emits CHANNEL_ERROR; call .subscribe() again to retry. Channels read kind-5 deletion events to accept deletion requests from other Nostr clients. For large deployments, use author filters and a relay with suitable retention and limits.