count distinct hour from datetime
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11-06-2021 - |
Domanda
I am working with sql database, and I have problem. It is about public transportation, and I have table 'Traffic accidents' and column 'Time when accident happened' (datetime). I need to count how many accidents happened in specific HOUR, to realize what is the most risking part of day. I know how to separate hour from datetime, but the problem is how to count and order.. It should be something like this:
Time of traffic accidents
2011-03-05 07:40:00.000,
2011-03-07 01:15:00.000,
2011-04-07 19:00:00.000,
2011-07-23 11:00:00.000,
2011-06-22 07:09:00.000,
2011-03-08 07:14:00.000,
2011-02-02 01:26:00.000
Order accidents by hour
7h- 3 accidents,
1h- 2 accidents,
6h- 1 accident,
etc…
My English is not perfect, but I hope that I was clear enough :P Thank you, Urosh
Soluzione
try something like this:
WITH T as
(
SELECT '2011-03-05 07:40:00.000' Col1 UNION ALL
SELECT '2011-03-07 01:15:00.000' Col1 UNION ALL
SELECT '2011-04-07 19:00:00.000' Col1 UNION ALL
SELECT '2011-07-23 11:00:00.000' Col1 UNION ALL
SELECT '2011-06-22 07:09:00.000' Col1 UNION ALL
SELECT '2011-03-08 07:14:00.000' Col1 UNION ALL
SELECT '2011-02-02 01:26:00.000'
)
Suppose T is your Table and Col1 is your datecolumn.
SELECT DATEPART(hour,Col1) as Hour,COUNT(DATEPART(hour,Col1)) as Accidents FROM T
GROUP BY DATEPART(hour,Col1)
ORDER BY DATEPART(hour,Col1)
Result:
Hour Accidents
1 2
7 3
11 1
19 1
Best Regards
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