SQL - Sum last value by date of current week - php

Question

I need to do a SUM of the last value (by date) of each day of the current week. To test I have a table with the values:
5 for 2023-01-12 16:53:01
2 for 2023-01-12 08:49:03
5 for 2023-01-11 08:58:19
I expect a result of 10.
I'm trying with the following code:
SELECT SUM(value) AS weeklyValue
FROM (
SELECT value
FROM table
WHERE WEEK(DATE(DataOra)) = WEEK(NOW())
AND WEEKDAY(DATE(DataOra)) >= 1
AND WEEKDAY(DATE(DataOra)) <= 7
AND DataOra = (SELECT MAX(DataOra) FROM table WHERE WEEKDAY(DataOra) = WEEKDAY(DATE(DataOra)) )
GROUP BY WEEKDAY(DATE(DataOra))
) AS subquery;
but the result is 5. Where is the mistake? Thanks

Answer 1

Maybe I found a solution:
SELECT SUM(Value) AS energiaSettimanale
FROM (
SELECT MAX(Value) as value, WEEKDAY(DataOra) as d
FROM table
WHERE WEEK(DATE(DataOra)) = WEEK(NOW())
AND WEEKDAY(DATE(DataOra)) >= 0
AND WEEKDAY(DATE(DataOra)) <= 6
GROUP BY d
) AS subquery;

Answer 2

If I really understood what you want, this request may be (if I understood correctly, I am specifying) the solution
select sum(value) from `table`
inner join (
select max(DataOra) as maxDataOra
from `table`
where WEEK(DATE(DataOra))=WEEK(NOW())
group by WEEKDAY(DataOra)
)
as tmp on DataOra=tmp.maxDataOra
The trick to find the most recent date of the day being to group by day number with the max() function on dateTime Data.

Answer 3

You can do it using inner join as follows :
select weekNumber, sum(value) from (
select t.value, week(s.maxDataOra) as weekNumber
from _table t
inner join (
select MAX(DataOra) as maxDataOra
from _table
group by DATE(DataOra)
) as s on s.maxDataOra = t.DataOra
) as b
group by weekNumber;
Check it here : https://dbfiddle.uk/hadzywwh

Answer 4

I need to do a SUM of the last value (by date) of each day of the current week.
So, let's start by constraining our working set to just the current week's data -
WHERE `DataOra` >= (CURRENT_DATE - INTERVAL(WEEKDAY(CURRENT_DATE)) DAY) /* first day of current week (Mon - Sun) */
AND `DataOra` < (CURRENT_DATE - INTERVAL(WEEKDAY(CURRENT_DATE)) DAY + INTERVAL 1 WEEK) /* first day of next week (Mon - Sun) */
Then we can use that to constrain the query used to get the MAX(DataOra) per DATE(DataOra) and join back to the original dataset to get the sum of the respective Values -
SELECT SUM(`Value`) `energiaSettimanale`
FROM `table` `t1`
INNER JOIN (
SELECT MAX(`DataOra`) AS `maxDataOra`
FROM `table`
WHERE `DataOra` >= (CURRENT_DATE - INTERVAL(WEEKDAY(CURRENT_DATE)) DAY) /* first day of current week (Mon - Sun) */
AND `DataOra` < (CURRENT_DATE - INTERVAL(WEEKDAY(CURRENT_DATE)) DAY + INTERVAL 1 WEEK) /* first day of next week (Mon - Sun) */
GROUP BY DATE(`DataOra`)
) `t2` ON `t2`.`maxDataOra` = `t1`.`DataOra`;
Or if using MySQL >= 8.0 you could use the ROW_NUMBER() window function -
SELECT SUM(`Value`) `energiaSettimanale`
FROM (
SELECT `Value`, ROW_NUMBER() OVER (PARTITION BY DATE(`DataOra`) ORDER BY `DataOra` DESC) `rn`
FROM `table`
WHERE `DataOra` >= (CURRENT_DATE - INTERVAL(WEEKDAY(CURRENT_DATE)) DAY) /* first day of current week (Mon - Sun) */
AND `DataOra` < (CURRENT_DATE - INTERVAL(WEEKDAY(CURRENT_DATE)) DAY + INTERVAL 1 WEEK) /* first day of next week (Mon - Sun) */
) `t`
WHERE `rn` = 1;