Question

I have a very simple table:

+----------+--------------+------+-----+---------+-------+
| Field    | Type         | Null | Key | Default | Extra |
+----------+--------------+------+-----+---------+-------+
| time     | int(11)      | YES  |     | 0       |       |
| username | varchar(120) | NO   | MUL |         |       |
| ip       | varchar(40)  | NO   | MUL |         |       |
| failed   | varchar(40)  | NO   | MUL |         |       |
+----------+--------------+------+-----+---------+-------+

I’m looking to query for a few specific users and I want both a count of logins and the most recent login (if any logins exist). I’ve tried various combinations of “GROUP BY” and nothing is quite working.

My simple count query is this:

mysql> SELECT count(*), username FROM logins WHERE username='[e-mail]' and failed='0' group by username;

How can I still get a single row back that contains both a count and the last login?

Bonus points if it turns the timestamp into human-friendly format.

edit: The first answer seems the clearest to me, and that worked well.

I also came up with this, which seems to work and returns in about the same amount of time, but I’m not sure what I’m doing there with the nested SELECT:

SELECT COUNT(*), username (SELECT MAX(time)) FROM logins WHERE username='[e-mail]' AND failed='0' GROUP BY username;

And to get a human-readable time:

SELECT COUNT(*), username (SELECT FROM_UNIXTIME(MAX(time))) FROM logins WHERE username='[e-mail]' AND failed='0' GROUP BY username;

Both this version and the more proper looking query in the first answer take about 2m 27s (the table has about 161M rows).

Answer 1

Max(time) will give you the latest login time. See the full query bellow

SELECT username, 
       COUNT(*)    AS `count`, 
       Max(`time`) AS `latest` 
FROM   logins 
WHERE  username = '[e-mail]' 
       AND failed = '0' 
GROUP  BY username;