This means for a DATEPART of SECOND, you get 4.3 billion seconds on either side, which works out to "anchor date ± 136 years." Similarly, 2 32 milliseconds is ≈ 49.7 days.ģ If your data actually spans centuries or millenia and is still accurate to the second or millisecond… congratulations! Whatever you're doing, keep doing it.Ĥ If you ever wondered why our clocks have a 12 at the top, reflect on how 5 is the only integer from 6 (half of 12) or below that is not a factor of 12. 4 As a counterexample, grouping results into 13-minute or 37-hour bins will skip some :00s, but it should still work fine.Ģ The math says 2 32 ≈ 4.29E+9. Your query will be totally unreadable, but it will work.ġ If you want all :00 timestamps to be eligible for binning, use an integer that your DATEPART's maximum can evenly divide into. DATEADD(DAY, DATEDIFF(DAY, 0, aa.), 0).Use one of the two replacements instead of '2000' wherever it appears in the query: For those queries, you can ask each row to anchor the binning comparison to its own date's midnight. If your data spans centuries, 3 using a single anchor date in the GROUP BY for seconds or milliseconds will still encounter the overflow. Most sample code uses 0 for the anchor, but JereonH discovered that you encounter an integer overflow when grouping more-recent dates by seconds or milliseconds. '2000' is an "anchor date" around which SQL will perform the date math. You will need to modify your GROUP BY to match, and you may want to use the whole ROUND(…) expression to avoid any unexpected float rounding. If you want to round your intervals inward such that each timestamp represents half an interval before and half an interval after it, use something like this: DATEADD(MINUTE, ROUND(1. ![]() End of interval: …) / 10 * 10 + 10, '2000'), credit to Daniel Elkington.If you want to label each row with the middle or end of its interval, you can tweak the division in the second term of DATEADD with the bold part below: The division ( /) operation after DATEDIFF truncates values to integers (a FLOOR shortcut), which yields the beginning of time intervals for each row in your SELECT output. ![]() Including it in the SELECT statement will give your output a single column with the truncated timestamp. Multiplying the GROUP BY expression by the interval size and wrapping it in a DATEADD invocation will return you a DATETIME value. Some other answers have collision between years. This means data sources over long time intervals are fine. The actual values being grouped are a set of relative offsets from 00:00. SELECT DATEADD(MINUTE, DATEDIFF(…) / * '2000') If you change the interval a lot, you might benefit from declaring it as a variable. For example, 10 with MINUTE is ten minute intervals 6 with HOUR is six hour intervals. The MINUTE and 10 terms can be changed to any DATEPART and integer, 1 respectively, to group into different time intervals. GROUP BY DATEDIFF(MINUTE, '2000', aa.) / 10ĭetails and extra commentary Bin interval size ![]() With heavy acknowledgements to Derek's answer, which forms the core of this one. Short and sweet GROUP BY DATEDIFF(MINUTE, '2000', date_column) / 10
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