MySQL 8.4

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CREATE TABLE habits (
  id INTEGER PRIMARY KEY AUTO_INCREMENT,
  name VARCHAR(32)
);

CREATE TABLE dates (
  d DATE PRIMARY KEY
);

INSERT INTO habits (name)
VALUES ('Journaling'), ('Yoga'), ('Meditation'), ('Go outside');

INSERT INTO dates (d)
VALUES ('2026-01-01'), ('2026-01-02'), ('2026-01-03'), ('2026-01-04'), ('2026-01-05'), ('2026-01-06'), ('2026-01-07');

Records: 4  Duplicates: 0  Warnings: 0



Records: 7  Duplicates: 0  Warnings: 0


select dates.d, habits.name
FROM dates INNER JOIN habits ON 1=1;


d
name


2026-01-01
Go outside

2026-01-01
Meditation

2026-01-01
Yoga

2026-01-01
Journaling

2026-01-02
Go outside

2026-01-02
Meditation

2026-01-02
Yoga

2026-01-02
Journaling

2026-01-03
Go outside

2026-01-03
Meditation

2026-01-03
Yoga

2026-01-03
Journaling

2026-01-04
Go outside

2026-01-04
Meditation

2026-01-04
Yoga

2026-01-04
Journaling

2026-01-05
Go outside

2026-01-05
Meditation

2026-01-05
Yoga

2026-01-05
Journaling

2026-01-06
Go outside

2026-01-06
Meditation

2026-01-06
Yoga

2026-01-06
Journaling

2026-01-07
Go outside

2026-01-07
Meditation

2026-01-07
Yoga

2026-01-07
Journaling


select count(*) FROM (
  select dates.d, habits.name
FROM dates INNER JOIN habits ON 1=1
  ) tmp;


count(*)


28

d	name
2026-01-01	Go outside
2026-01-01	Meditation
2026-01-01	Yoga
2026-01-01	Journaling
2026-01-02	Go outside
2026-01-02	Meditation
2026-01-02	Yoga
2026-01-02	Journaling
2026-01-03	Go outside
2026-01-03	Meditation
2026-01-03	Yoga
2026-01-03	Journaling
2026-01-04	Go outside
2026-01-04	Meditation
2026-01-04	Yoga
2026-01-04	Journaling
2026-01-05	Go outside
2026-01-05	Meditation
2026-01-05	Yoga
2026-01-05	Journaling
2026-01-06	Go outside
2026-01-06	Meditation
2026-01-06	Yoga
2026-01-06	Journaling
2026-01-07	Go outside
2026-01-07	Meditation
2026-01-07	Yoga
2026-01-07	Journaling