Without touching the table

Return the actor_id of every event for actor 200 — that column and nothing else, ordered by actor_id. The index already carries everything you need, so the table should never be read.

Tables in this database · Events

CREATE TABLE events (
  id INTEGER PRIMARY KEY,
  actor_id INTEGER NOT NULL,
  kind TEXT NOT NULL,
  email TEXT NOT NULL,
  happened_on DATE NOT NULL,
  duration_ms INTEGER
)

CREATE INDEX events_actor_idx ON events (actor_id);
CREATE INDEX events_kind_happened_idx ON events (kind, happened_on);
CREATE INDEX events_email_idx ON events (email);

Your query

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