psql select unique
snippet in sql

postgresql left join distinct on

user7407

Select Distinct On (u.username, u.email)
     u.username
    ,u.email
    ,l.browser
    ,l.login_time
From users u
Join logins l On l.username = u.username
Order By u.username, u.email, login_time Desc
 
                                        ^

psql select unique

user9646

SELECT
   DISTINCT column1
FROM
   table_name;