db.startCleanerLocked()
}

// startCleanerLocked starts connectionCleaner if needed.
func (db *DB) startCleanerLocked() {
	if (db.maxLifetime > 0 || db.maxIdleTime > 0) && db.numOpen > 0 && db.cleanerCh == nil {
		db.cleanerCh = make(chan struct{}, 1)
		go db.connectionCleaner(db.shortestIdleTimeLocked())
	}
}

func (db *DB) connectionCleaner(d time.Duration) {
	const minInterval = time.Second

	tx, err = db.Begin()
	if err != nil {
		t.Fatal(err)
	}
	tx2, err = db.Begin()
	if err != nil {
		t.Fatal(err)
	}
	tx.Commit()
	tx2.Commit()

	// Give connectionCleaner chance to run.
	waitCondition(t, func() bool {
		driver.mu.Lock()
		opens = driver.openCount - opens0
		closes = driver.closeCount - closes0
		driver.mu.Unlock()

		return closes == 1
	})