The DATEDIFF function of the query language is intended to get the difference between two dates in a specified measurement unit. The syntax of the function is as follows:
DATEDIFF(<Expression>, <Expression>, Second | Minute | Hour | Day | Month | Quarter | Year)
The first parameter value is subtracted from the second parameter value.
The third parameter defines the measurement unit for the function result. You can use the following values in the third parameter: Second, Minute, Hour, Day, Month, Quarter, and Year. When calculating the result, the function ignores the measurement units that are smaller than the one specified in this parameter.
For example, if you specify Hour in the third parameter, minutes and seconds in the first two parameters are ignored. If you specify Month in the third parameter, then days, hours, minutes, and seconds are ignored.
The following table provides examples of the function return values:
| Function | Result |
|---|---|
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), SECOND) |
82 652 |
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), MINUTE) |
1 378 |
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), HOUR) |
23 |
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), DAY) |
1 |
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), MONTH) |
1 |
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), QUARTER) |
1 |
| DATEDIFF(DATETIME(2002, 12, 31, 10, 20, 34), DATETIME(2003, 01, 01, 9, 18, 06), YEAR) |
1 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), SECOND) |
31 535 999 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), MINUTE) |
525 599 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), HOUR) |
8 759 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), DAY) |
364 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), MONTH) |
11 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), QUARTER) |
3 |
| DATEDIFF(DATETIME(2002, 01, 01, 0, 0, 0), DATETIME(2002, 12, 31, 23, 59, 59), YEAR) |
0 |
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