Time difference without considering times between 0am ~ 4am. MySQL - mysql

MySQL version 8.0
I want to calculate time difference between two datetime column.
And get rows where duration >= 12:00:00.
which I would normally do:
select id
, start_time
, end_time
, timediff(end_time, start_time) as duration
from table;
which I would get something like this:
id start_time end_time duration
0 1 2020-06-01 01:00:00 2020-06-01 14:00:00 13:00:00
1 2 2020-06-01 01:00:00 2020-06-01 18:00:00 17:00:00
2 3 2020-06-01 19:00:00 2020-06-02 10:00:00 15:00:00
3 4 2020-06-02 04:00:00 2020-06-02 16:00:00 12:00:00
For duration column I don't want times between 00:00:00 ~ 04:00:00 to be added towards the duration. So for the first row duration = 10:00:00 since 01:00:00~14:00:00 = 10:00:00, ignoring times between 00:00:00 ~ 04:00:00
same for second row we substract 3 hours from duration.
so my desired output would be:
id start_time end_time duration
0 1 2020-06-01 01:00:00 2020-06-01 14:00:00 10:00:00
1 2 2020-06-01 01:00:00 2020-06-01 18:00:00 14:00:00
2 3 2020-06-01 19:00:00 2020-06-02 10:00:00 11:00:00
3 4 2020-06-02 04:00:00 2020-06-02 16:00:00 12:00:00
There are lots of rows where times include minutes and seconds too.
Thanks in advance!
I've grabbed all rows where duration >= 12:00:00.
Then separated data into 4 regions depending on their start_time.
a_region = 00~04
b_region = 04~12
c_region = 12~16
d_region = 16~24
For a_region I've subtracted 04:00:00 - start_time which is time we should compensate to duration in a_region.
compensation = 04:00:00 - start_time
compensated_time = duration - compensation.
For b_region it needs no compensation if it has passed 00~04 it means it already passed duration = 12:00:00.
For c_region,
compensation = 16:00:00 - start_time
compensated_time = duration - compensation
For d_region since we've grabbed duration >= 12:00:00
it will pass all of 00~04 therefore
compensated_time = duration - 04:00:00.
I solved it using Python but above is the logic I've used.

One option uses greatest():
select id
, start_time
, end_time
, timediff(
greatest(,
end_time,
date_format(end_time, '%Y-%m-%d 04:00:00')
),
greatest(
start_time,
date_format(start_time, '%Y-%m-%d 04:00:00')
)
) as duration
from table;

Related

Diff between values in different rows

MariaDB version 10.4.10.
I have a stock scraper script that fetches stock data every hour and inserts it into a MySQL database. The database structure is similar to this:
stocks( time_fetched DATETIME, fetch_id INT, name VARCHAR, price INT )
And some example data:
**time_fetched fetch_id name price**
2020-03-10 09:00:00 1 stock1 10
2020-03-10 09:00:00 1 stock2 15
2020-03-10 10:00:00 2 stock1 12
2020-03-10 10:00:00 2 stock2 20
2020-03-10 11:00:00 3 stock1 8
2020-03-10 11:00:00 3 stock2 18
I want a way to get price change for each stock between, say, stocks fetched at 09:00 and 10:00, or between 09:00 and 11:00. Something like this (pseudo code):
SELECT *, DIFF( current_price, price_one_hour_ago) AS change_1h, DIFF( current_price, price_two_hours_ago) AS change_2h
Is it possible to do this directly in MySQL? I am using a PHP script to display the data, so I might have to resort to do it in PHP instead.
You can use a CTE to generate prices delayed by 1 or 2 hours, and then compute the changes using those values (potentially using COALESCE to make NULL values into 0):
WITH prices AS (
SELECT time_fetched, name, price,
LAG(price, 1) OVER(PARTITION BY name ORDER BY time_fetched) AS price_1h,
LAG(price, 2) OVER(PARTITION BY name ORDER BY time_fetched) AS price_2h
FROM stocks
)
SELECT time_fetched, name, price,
COALESCE(price - price_1h, 0) AS change_1h,
COALESCE(price - price_2h, 0) AS change_2h
FROM prices
Output:
time_fetched name price change_1h change_2h
2020-03-10 09:00:00 stock1 10 0 0
2020-03-10 10:00:00 stock1 12 2 0
2020-03-10 11:00:00 stock1 8 -4 -2
2020-03-10 09:00:00 stock2 15 0 0
2020-03-10 10:00:00 stock2 20 5 0
2020-03-10 11:00:00 stock2 18 -2 3
Demo on dbfiddle also showing query results without COALESCE.

MariaDb/MySQL sliding sum over 24 hours

My table have fields that represent starting and ending working period as datetime.
I need to find related entries that match a total of 14hours min over a sliding period of 24 hours.
I think window function will (maybe) save me, but MariadDB (i use) doesn't implement yet Range time intervals in window function.
here is some example data:
id starting_hour ending_hour
-- ------------------- -------------------
1 2018-09-02 06:00:00 2018-09-02 08:30:00
2 2018-09-03 08:30:00 2018-09-03 10:00:00
4 2018-09-03 11:00:00 2018-09-03 15:00:00
5 2018-09-02 15:30:00 2018-09-02 16:00:00
6 2018-09-02 16:15:00 2018-09-02 17:00:00
7 2018-09-20 00:00:00 2018-09-20 08:00:00
8 2018-09-19 10:00:00 2018-09-19 12:00:00
9 2018-09-19 12:00:00 2018-09-19 16:00:00
10 2018-10-08 12:00:00 2018-10-08 14:00:00
11 2018-10-29 09:00:00 2018-10-29 10:00:00
So how to find rows where in a 24 hours window their sum a more or equal to 14 hours.
thanks
Edit:
SELECT
id,
starting_hour,
ending_hour,
TIMEDIFF (ending_hour, starting_hour) AS duree,
(
SELECT SUM(TIMEDIFF(LEAST(ending_hour, DATE_ADD(a.starting_hour, INTERVAL 24 HOUR)), starting_hour)) / 10000
FROM `table` b
WHERE b.starting_hour BETWEEN a.starting_hour AND DATE_ADD(a.starting_hour, INTERVAL 24 HOUR)
) AS duration
FROM
`table` a
HAVING duration >= 14
ORDER BY starting_hour ASC
;
This returns Id 8 but i want the whole period. (eg: Id 8, Id 9 and Id 7)
EDIT2:
The expected results are ranges of working time where they are in a window of 24 hours and where their sum are more or equal to 14 hours.
EDIT 3:
In fact under MySQL 8 this seems to work.
SELECT * FROM (
SELECT
*,
SEC_TO_TIME(SUM(TIME_TO_SEC(TIMEDIFF(hs.`ending_hour`, hs.`starting_hour`))) OVER (ORDER BY hs.starting_hour RANGE BETWEEN INTERVAL '12' HOUR PRECEDING AND INTERVAL '12' HOUR following)) AS tot
FROM
table hs
WHERE hs.`starting_hour` > DATE_SUB(NOW(), INTERVAL 50 DAY) AND hs.`ending_hour` <= NOW()
ORDER BY hs.`starting_hour` ASC
) t1
HAVING tot >= '14:00:00'
;
Is there a way to do it under MariaDB 10.2 without window function ? Or without window range function ?

How to get time wise Record in mysql

I need Time Wise Sales Report in mysql,I get the Report like
Time Amount
19:00:00 2
20:00:00 5
21:00:00 0
22:00:00 0
23:00:00 14
but I need sum of Amount like
Time Amount
19:00:00 2
20:00:00 5
21:00:00 5
22:00:00 5
23:00:00 14
This is my Query
SELECT concat(MID(date_of_call, 12, 2),':00:00') TimeIntervel,COUNT(*) TotalEntries,date_format(date_of_call,'%d/%m/%Y') FROM ICC_MM_setup_suply
WHERE DATE_FORMAT(date_of_call,'%d/%m/%Y')='31/01/2017'
GROUP BY concat(MID(date_of_call, 12, 2),':00:00')
You can use User variables:
set #lastval := 0;
select
time,
#lastval := if(Amount = 0, #lastval, Amount) Amount
from t
order by time;

How to find sales per hour between two date

Suppose I have 5 records for a sales table.
ID Name datetime_col
1 ABC 2016-09-15 02:07:56
2 HSJ 2016-09-31 11:45:45
3 JSD 2016-11-26 07:09:56
4 JUH 2016-12-31 12:00:00
5 IGY 2017-01-13 14:00:07
I want to find how many records are there in sales table for each hour between 2016-09-15 AND 2017-01-13
Then result should be like
Hour sales_at_this_hour
2016-09-15 01:00:00 0
2016-09-15 02:00:00 1
2016-09-15 03:00:00 0
...
...
2017-01-13 01:00:00 0
2017-01-13 02:00:00 0
2017-01-13 03:00:00 0
....
2017-01-13 14:00:00 1
Then find the average of sales_at_this_hour using MySQL
EDIT: sorry not fully understand the question at first.
Use DATE_FORMAT
select
DATE_FORMAT(datetime_col, '%Y-%m-%d %h:00:00') as date,
count(id) as count
from table_name
group by date;
Get result with hours that has sales_at_this_hour > 1 (not exactly what you ask for)
datetime_col count
2016-02-04 05:00:00 5
2016-02-04 07:00:00 1
2016-02-04 08:00:00 5
2016-02-04 10:00:00 10
2016-02-04 11:00:00 1
Provide start_date and end_date, and then use DATEDIFF to calculate total time interval for the average calculation.
set #start_date = '2016-01-01', #end_date = '2017-01-01';
select
DATE_FORMAT(group_by_date.datetime, '%h:00:00') as hour,
AVG(group_by_date.count) / DATEDIFF(#end_date, #start_date) as average
from (
select
DATE_FORMAT(created_dtm, '%Y-%m-%d %h:00:00') as datetime,
count(id) as count
from table_name
where created_dtm > #start_date
and created_dtm < #end_date
group by datetime
) group_by_date
group by hour;
For each hour,
average sale count per day = total sale count / total days
hour average
01:00:00 0.03841209
02:00:00 0.01653005
03:00:00 0.0306716
04:00:00 0.01147541
05:00:00 0.01179831

MySQL get list of start time and end time conflict

Need help for MySQL query for retrieving record of class schedule that is conflict in the given time.
Ex.
SchedID StartTime EndTime
1 09:00:00 13:00:00
2 08:30:00 10:00:00
3 11:00:00 15:00:00
4 07:30:00 08:30:00
5 11:30:00 13:00:00
I would like to retrieve the list that is conflict in this given time
Start Time = 09:00:00
End Time = 11:00:00
The record will yield following result:
SchedID StartTime EndTime
1 09:00:00 13:00:00
2 08:30:00 10:00:00
3 11:00:00 15:00:00
Thank you.
Try this
SELECT DISTINCT a.schedid, a.starttime, a.endtime
FROM
tbl_name a, tbl_name b
WHERE ((b.starttime > a.starttime AND b.starttime < a.endtime)
OR (b.endtime > a.starttime AND b.endtime < a.endtime))
ORDER BY schedid
i just found my answer here Determine Whether Two Date Ranges Overlap
Heres my query:
SELECT * FROM tableName WHERE (start_time < givenEndTime)
AND (end_time > givenStartTime);
This works perfectly fine for me.