rockset> SELECT
             user.user.name
         FROM
             twitter_collection AS col,
             UNNEST(col.entities.user_mentions AS user) AS user
         WHERE
             typeof(user.user.name) = 'string'
         GROUP BY
             user.user.name
         ORDER BY
             COUNT(*) DESC
         LIMIT 5;
+---------------------+
| name                |
|---------------------|
| 방탄소년단             |
| Michelle Obama      |
| H.E.R.              |
| lego                |
| BT21                |
+---------------------+