select * from sends;

 id |   email_address   |          sent_at
----+-------------------+----------------------------
  1 | jerry@outlook.com | 2017-07-01 02:24:53.902052
  2 | tom@yahoo.com     | 2017-07-01 02:24:53.902052
  3 | jerry@outlook.com | 2017-07-02 02:24:53.938798
  4 | tom@yahoo.com     | 2017-07-02 02:24:53.938798
... abridged ...
 17 | jerry@yahoo.com   | 2017-07-11 02:25:09.996991
 18 | tom@aol.com       | 2017-07-11 02:25:09.996991
(18 rows)