Question

Table users

• id – Primary Key, AI
• username – varchar (50)

Table logins

• login_time – DateTime
• member_id – int (11)

This SQL selects mid and max login_time and sorts DESC
SELECT member_id, max(login_time) as time FROM logins
GROUP BY member_id
ORDER BY time DESC

Question
How do you select and join username onto member_id for each row?

Answer 1

SELECT u.username, max(l.login_time) as time FROM logins l
LEFT JOIN users u ON (l.member_id = u.id)
GROUP BY l.member_id ORDER BY time DESC