CREATE TABLE price_history (

    event_id    BIGINT NOT NULL REFERENCES events(id) ON DELETE CASCADE,

    source      TEXT NOT NULL,

    observed_at TIMESTAMPTZ NOT NULL,

    price_min   INTEGER,

    price_max   INTEGER,

    currency    CHAR(3)

);

CREATE INDEX idx_price_event_time ON price_history(event_id, observed_at DESC);

CREATE TABLE source_health (

    source_id       TEXT NOT NULL,

    observed_at     TIMESTAMPTZ NOT NULL,

    ok              BOOLEAN NOT NULL,

    latency_ms      INTEGER NOT NULL CHECK (latency_ms >= 0),

    events_returned INTEGER NOT NULL DEFAULT 0,

    error           TEXT

);

CREATE INDEX idx_health_source_time ON source_health(source_id, observed_at DESC);