StackOverflow question #38874837, MySQL

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DROP TABLE IF EXISTS foo;
    CREATE TABLE foo (user_id INT, time_start DATETIME, some_count INT);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (1, '2016-07-27 12:54:36', 3);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (1, '2016-07-27 11:23:45', 11);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (1, '2016-07-27 13:24:12', 11);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (1, '2016-07-27 07:51:22', 11);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (1, '2016-07-27 19:22:13', 4);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (2, '2016-07-27 12:54:37', 3);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (2, '2016-07-27 11:23:46', 1);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (2, '2016-07-27 13:24:13', 1);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (2, '2016-07-27 07:51:23', 1);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (2, '2016-07-27 19:22:14', 4);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (3, '2016-07-27 12:54:38', 3);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (3, '2016-07-27 11:23:47', 210);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (3, '2016-07-27 13:24:14', 210);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (3, '2016-07-27 07:51:24', 210);
    INSERT INTO foo (user_id, time_start, some_count) VALUES (3, '2016-07-27 19:22:15', 4);

SELECT time_start, some_count
    FROM foo f1
    WHERE DATE(time_start) = '2016-07-27'
      AND CONCAT(LPAD(some_count, 10, '0'), time_start) = 
          (SELECT MAX(CONCAT(LPAD(some_count, 10, '0'), time_start))
           FROM foo f2
           WHERE DATE(f2.time_start) = '2016-07-27'
             AND f2.user_id = f1.user_id);


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