MariaDB 10.3

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CREATE TABLE `plant_data` (
    `id` BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
    `plant_id` BIGINT(20) UNSIGNED NOT NULL,
    `temperature` DECIMAL(5,1) UNSIGNED NOT NULL,
    `light` SMALLINT(5) UNSIGNED NOT NULL,
    `created_at` TIMESTAMP NULL DEFAULT NULL,
    `updated_at` TIMESTAMP NULL DEFAULT NULL,
    PRIMARY KEY (`id`)
);
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1623, 14, 22.2, 35, '2020-02-16 09:00:06', '2020-02-16 09:00:06');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1622, 5, 22.8, 33, '2020-02-16 09:00:06', '2020-02-16 09:00:06');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1621, 14, 22.8, 36, '2020-02-16 08:00:07', '2020-02-16 08:00:07');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1620, 5, 23.3, 33, '2020-02-16 08:00:07', '2020-02-16 08:00:07');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1619, 14, 23.1, 36, '2020-02-15 07:00:11', '2020-02-15 07:00:11');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1618, 5, 23.8, 34, '2020-02-15 07:00:11', '2020-02-15 07:00:11');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1617, 14, 24.4, 38, '2020-02-15 06:00:09', '2020-02-15 06:00:09');
INSERT INTO `plant_data` (`id`, `plant_id`, `temperature`, `light`, `created_at`, `updated_at`) VALUES (1616, 5, 24.6, 34, '2020-02-15 06:00:09', '2020-02-15 06:00:09');
SELECT plant_id, date(created_at) as day, avg(temperature) 
FROM plant_data 
WHERE created_at >= '2020-02-15 00:00:00' 
  AND created_at <= '2020-02-17 00:00:00' 
GROUP BY plant_id, date(created_at);


plant_id
day
avg(temperature)


5
2020-02-15
24.20000

5
2020-02-16
23.05000

14
2020-02-15
23.75000

14
2020-02-16
22.50000


SELECT plant_id, date(created_at) as day, avg(temperature) 
FROM plant_data 
WHERE created_at BETWEEN '2020-02-15 00:00:00' 
                     AND '2020-02-17 00:00:00' 
GROUP BY plant_id, date(created_at);


plant_id
day
avg(temperature)


5
2020-02-15
24.20000

5
2020-02-16
23.05000

14
2020-02-15
23.75000

14
2020-02-16
22.50000


SELECT plant_id, date(created_at) as created_date, avg(temperature) 
FROM plant_data 
WHERE created_at BETWEEN '2020-02-15 00:00:00' 
                     AND '2020-02-17 00:00:00' 
GROUP BY plant_id, date(created_at);


plant_id
created_date
avg(temperature)


5
2020-02-15
24.20000

5
2020-02-16
23.05000

14
2020-02-15
23.75000

14
2020-02-16
22.50000
plant_id	day	avg(temperature)
5	2020-02-15	24.20000
5	2020-02-16	23.05000
14	2020-02-15	23.75000
14	2020-02-16	22.50000