presto-main/src/main/java/io/prestosql/operator/scalar/DateTimeFunctions.java/DateTimeFunctions/yearFromInterval
class DateTimeFunctions:    @Description("year of the given interval")
    @ScalarFunction("year")
    @SqlType(StandardTypes.BIGINT)
    public static long yearFromInterval(@SqlType(StandardTypes.INTERVAL_YEAR_TO_MONTH) long months)
    {
        return months / 12;
    }