The datetime value function DateTimeLib.intervalValueWithPattern returns an INTERVAL value that reflects a string constant or literal and (optionally) is built based on an interval mask that you specify. If the mask is yyyy, for example, the input string must contain four digits, and those digits represent the number of years represented in the interval.
DateTimeLib.intervalValueWithPattern( intervalAsString STRING in [, intervalMask STRING in ]) returns (result INTERVAL)
Related concepts
Syntax diagram for EGL functions
Related reference
Datetime expressions
INTERVAL