Interval literals

Interval literals define an interval value in an expression.

Syntax 1: year-month class interval

 INTERVAL ( inrep ) YEAR[(precision)] TO MONTH
|INTERVAL ( inrep ) YEAR[(precision)] TO YEAR
|INTERVAL ( inrep ) MONTH[(precision)] TO MONTH

Syntax 2: day-time class interval

 INTERVAL ( inrep ) DAY[(precision)] TO FRACTION[(scale)]
|INTERVAL ( inrep ) DAY[(precision)] TO SECOND
|INTERVAL ( inrep ) DAY[(precision)] TO MINUTE
|INTERVAL ( inrep ) DAY[(precision)] TO HOUR
|INTERVAL ( inrep ) DAY[(precision)] TO DAY

|INTERVAL ( inrep ) HOUR[(precision)] TO FRACTION[(scale)]
|INTERVAL ( inrep ) HOUR[(precision)] TO SECOND
|INTERVAL ( inrep ) HOUR[(precision)] TO MINUTE
|INTERVAL ( inrep ) HOUR[(precision)] TO HOUR

|INTERVAL ( inrep ) MINUTE[(precision)] TO FRACTION[(scale)]
|INTERVAL ( inrep ) MINUTE[(precision)] TO SECOND
|INTERVAL ( inrep ) MINUTE[(precision)] TO MINUTE

|INTERVAL ( inrep ) SECOND[(precision)] TO FRACTION[(scale)]
|INTERVAL ( inrep ) SECOND[(precision)] TO SECOND

|INTERVAL ( inrep ) FRACTION TO FRACTION[(scale)]

inrep is the interval value representation in normalized format (YYYY-MM or DD hh:mm:ss.fffff, according to the interval class).

Usage

An interval literal is specified with the INTERVAL() notation, and is typically used to assign in interval or datetime expressions, or to assign an interval variable.

Example

MAIN
  DEFINE i1 INTERVAL YEAR TO MONTH
  DEFINE i2 INTERVAL HOUR(5) TO SECOND
  LET i1 = INTERVAL( 345-5 ) YEAR TO MONTH
  LET i2 = INTERVAL( 34562:22:33 ) HOUR(5) TO SECOND
END MAIN