Finding business minutes between two dates - snowflake-cloud-data-platform

Question

I am working on finding a solution of date difference down to the minute for business hours. I have a table that provides every date and a 1/0 column next to it as a business day. Additionally, I know (not in table) the working hours is 8:00 to 16:00. What I am having issues with is pulling in this column that has a 1 for business days and then adding in those hours and finding true date differences to the minute. On top of that, I am trying to find a solution of off hours time stamps. Ideas behind lets say 7:32:00 on 6/20/22 and 17:42:00 on 6/24/22 with a work holiday on 6/23/22. This is all done in snowflake for now.

Answer 1

I think this SQL should solve the problem.
In the CTE you need to put in the timestamp-columns, which you want to use as the borders for your business-minutes calculation. It will then calculate how many business dates are between the two border timestamps.
In the second query it will first calculate the difference between the timestamps if they are not on the same date. Afterwards there is another CASE block that will handle the cases, if the timestamps are on the same date.
CREATE OR REPLACE TABLE TEST.BUSINESS_DATES
AS
SELECT TO_DATE('2022-12-29') AS REF_DATE, 1 AS BUSINESS_DATE_INDICATOR
UNION ALL
SELECT TO_DATE('2022-12-30') AS REF_DATE, 1 AS BUSINESS_DATE_INDICATOR
UNION ALL
SELECT TO_DATE('2022-12-31') AS REF_DATE, 0 AS BUSINESS_DATE_INDICATOR
UNION ALL
SELECT TO_DATE('2023-01-01') AS REF_DATE, 0 AS BUSINESS_DATE_INDICATOR
UNION ALL
SELECT TO_DATE('2023-01-02') AS REF_DATE, 1 AS BUSINESS_DATE_INDICATOR
UNION ALL
SELECT TO_DATE('2023-01-03') AS REF_DATE, 0 AS BUSINESS_DATE_INDICATOR
UNION ALL
SELECT TO_DATE('2023-01-04') AS REF_DATE, 1 AS BUSINESS_DATE_INDICATOR
;
WITH PRE_INTERVALS AS
(SELECT
SUM(BUSINESS_DATE_INDICATOR) AS NUMBER_BUSINESS_DATES,
TO_TIMESTAMP_NTZ('2022-12-30 13:44:00') AS START_TS,
TO_TIMESTAMP_NTZ('2023-01-04 17:33:00') AS END_TS
FROM TEST.BUSINESS_DATES
WHERE REF_DATE BETWEEN TO_DATE(START_TS) AND TO_DATE(END_TS))
SELECT
CASE
WHEN TIME(START_TS) BETWEEN TO_TIME('08:00:00') AND TO_TIME('16:00:00')
THEN DATEDIFF('minutes', TO_TIME(START_TS), TO_TIME('16:00:00'))
WHEN TIME(START_TS) < TO_TIME('08:00:00')
THEN 480
WHEN TIME(START_TS) > TO_TIME('16:00:00')
THEN 0
END AS FIRST_DAY_MINUTES,
CASE
WHEN TIME(END_TS) BETWEEN TO_TIME('08:00:00') AND TO_TIME('16:00:00')
THEN DATEDIFF('minutes', TO_TIME('08:00:00'), TO_TIME(END_TS))
WHEN TIME(END_TS) < TO_TIME('08:00:00')
THEN 0
WHEN TIME(END_TS) > TO_TIME('16:00:00')
THEN 480
END AS LAST_DAY_MINUTES,
CASE
WHEN TO_DATE(START_TS) = TO_DATE(END_TS)
THEN
CASE
WHEN NUMBER_BUSINESS_DATES = 0
THEN 0
WHEN TIME(START_TS) BETWEEN TO_TIME('08:00:00') AND TO_TIME('16:00:00') AND TIME(END_TS) BETWEEN TO_TIME('08:00:00') AND TO_TIME('16:00:00')
THEN DATEDIFF('minutes', TO_TIME(START_TS), TO_TIME(END_TS))
WHEN TIME(START_TS) < TO_TIME('08:00:00') AND TIME(END_TS) > TO_TIME('16:00:00')
THEN 480
WHEN TIME(START_TS) < TO_TIME('08:00:00')
THEN DATEDIFF('minutes', TO_TIME('08:00:00'), TO_TIME(END_TS))
WHEN TIME(END_TS) > TO_TIME('16:00:00')
THEN DATEDIFF('minutes', TO_TIME(START_TS), TO_TIME('16:00:00'))
END
ELSE
(NUMBER_BUSINESS_DATES - 2) * 480 + FIRST_DAY_MINUTES + LAST_DAY_MINUTES
END AS DIFF_BUSINESS_MINUTES
FROM PRE_INTERVALS;
Best regards,
TK