Calendar duration functions

Use duration functions to define and compute calendar durations.
Table 1. Functions for calendar durations
Syntax Description Example
<number> <time unit>
Returns a calendar duration in years, months, days, hours, minutes, or seconds.
7 months
<date & time> - <calendar duration>
Returns a new time point that precedes the specified time point by the specified duration.
the beginning of training - 1 month
<date & time> + <calendar duration>
Returns a new time point that follows the specified time point by the specified duration.
the beginning of training + 1 month
<calendar duration> + <calendar duration>
Returns a calendar duration that corresponds to the sum of the two durations.
the duration of training + the duration of certification