5 minutes to read 12.
T sql floor date time in 5 minute window.
Well not earlier but it is here today about how to create a function to round up time to nearest minute interval.
Recently i was asked if i have written a function which rounds up or down the time based on the minute interval passed to it.
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In the select add 5 times the number of 5 minute intervals back to the fix date to get the start of the 5 minute period.
Floor a datetime in sql server suppose you are given a datetime and want to emulate the floor function on it eg.
See date and time data types and functions transact sql for an overview of all.
For example using the lag function is so much better than doing a self join.
My method will work on seconds minutes hours and can be adapted to weeks months.
This convert the period to date time format select note the 5 the minute and the starting point to convert the period back to original time dateadd minute ap fiveminutesperiod 5 2010 01 01t00 00 00 as period ap avgvalue from this groups by the period and gets the average select p fiveminutesperiod avg p value as.
2 minutes to read 5.
It only works on rounding up or down to the nearest day.
Sql server all supported versions azure sql database azure sql managed instance azure synapse analytics parallel data warehouse this function returns an integer representing the specified datepart of the specified date.
Sql server all supported versions azure sql database azure sql managed instance azure synapse analytics parallel data warehouse returns the largest integer less than or equal to the specified numeric expression.
To get better performance overall however you need to understand the concept of framing and how window functions rely on sorting to provide the results.
There s a couple reasons why i don t go that route.
T sql window functions make writing many queries easier and they often provide better performance as well over older techniques.
