code: func showKeyTTL(iter *gocql.Iter, groupTTL string) {
  	roundTTL := 1
  	switch groupTTL {
  	case "m":
  		roundTTL = 60
  	case "h":
  		roundTTL = 60 * 60
  	case "d":
  		roundTTL = 60 * 60 * 24
  	}
  
  	var b bucket
  	bucketMap := make(map[bucket]int)
  	for iter.Scan(&b.key, &b.ttl) {
  		b.ttl /= roundTTL
  		bucketMap[b] += 1
  	}
  
  	var bucketList []bucketWithCount
  	for b, count := range bucketMap {
  		bucketList = append(bucketList, bucketWithCount{
  			b.key,
  			b.ttl,
  			count,
  		})
  	}
  
  	sort.Sort(byTTL(bucketList))
  	for _, b := range bucketList {
  		fmt.Printf("%s %d%s %d\n", b.key, b.ttl, groupTTL, b.c)
  	}
  	err := iter.Close()
  	if err != nil {
  		log.Errorf("cassandra query error. %s", err)
  	}
  }
docs: // shows an overview of all keys and their ttls and closes the iter
  // iter must return rows of key and ttl.