MySQL 8.0

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create table daily_stats (`date` date, stat int, value int);
insert into daily_stats values
('2019-01-27',132,62),
('2019-01-28',132,64),
('2019-01-29',132,65),
('2019-01-30',132,66),
('2019-01-29',120,21),
('2019-01-30',120,21),
('2019-01-28',111,7),
('2019-01-29',111,7);
WITH RECURSIVE
dates (date) AS 
    (
      SELECT CAST('2019-01-24' AS date)
      UNION ALL
      SELECT  date + INTERVAL 1 DAY
      FROM dates
      WHERE date <= DATE_SUB('2019-01-30', INTERVAL 1 DAY)
    ),
s (ord, stat) AS
    ( SELECT 1, 132 UNION ALL
      SELECT 2, 120 UNION ALL
      SELECT 3, 111
    )
SELECT
    dates.date AS label,
    GROUP_CONCAT(COALESCE(ds.value, '0') ORDER BY s.ord) AS value
FROM dates
CROSS JOIN s
LEFT JOIN daily_stats AS ds
  ON  ds.stat = s.stat
  AND ds.date = dates.date
GROUP BY dates.date ;


label
value


2019-01-24
0,0,0

2019-01-25
0,0,0

2019-01-26
0,0,0

2019-01-27
62,0,0

2019-01-28
64,0,7

2019-01-29
65,21,7

2019-01-30
66,21,0

label	value
2019-01-24	0,0,0
2019-01-25	0,0,0
2019-01-26	0,0,0
2019-01-27	62,0,0
2019-01-28	64,0,7
2019-01-29	65,21,7
2019-01-30	66,21,0