select 1+1 in (1,2,3,4);
select (1+1) in (1,2,3,4);
select true=false in (true,false);
select false=false in (true,false);
select interval '5-5' year to month;

select
	(1) second,
	 2  seconds,
	(1) minute,
	 2  minutes,
	(1) hour,
	 2  hours,
	(1) day,
	 2  days,
	(1) month,
	 2  months,
	(1) year,
	 2  years;

select date '2012-01-01' + 30 days;
select date '2012-01-01' - 30 days;

create table t_n18 (dt int);
insert into t_n18 values (1),(2);

-- expressions/columnref
explain
select
	date '2012-01-01' + interval (-dt*dt) day,
	date '2012-01-01' - interval (-dt*dt) day,
	date '2012-01-01' + 1 day + '2' days,
	date '2012-01-01' + interval (dt || '-1') year to month
	from t_n18;

select
        date '2012-01-01' + interval (-dt*dt) day,
        date '2012-01-01' - interval (-dt*dt) day,
        date '2012-01-01' + 1 day + '2' days,
        date '2012-01-01' + interval (dt || '-1') year to month
        from t_n18;