Postgres 14

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CREATE TABLE tab(
	app   	VARCHAR(30),     
  	people  VARCHAR(30),
  	login   DATE
);

CREATE TABLE


INSERT INTO tab VALUES
('slack',      'Jenny',           '2019-01-01'),         
('slack',      'Jenny',           '2020-01-01'),      
('slack',      'Jenny',           '2021-01-01'),
('slack',       'Yang',           '2020-06-01'),      
('slack',       'Yang',           '2021-06-01');

INSERT 0 5


select distinct on (app,people)
app, people, login from tab
order by app, people, login desc


app
people
login


slack
Jenny
2021-01-01

slack
Yang
2021-06-01



SELECT 2