create or replace function add5 (n number)

returns number

as 'n + 5';

create or replace function add5 (s string)

returns string

as 's || ''5''';

create function area_of_circle(radius float)

returns float

as

$$

pi() * radius * radius

$$

;

select area_of_circle(1.0);

create table purchases (number_sold integer, wholesale_price number(7,2), retail_price number(7,2));

insert into purchases (number_sold, wholesale_price, retail_price) values

(3, 10.00, 20.00),

(5, 100.00, 200.00)

;

create function profit()

returns numeric(11, 2)

as

$$

select sum((retail_price - wholesale_price) * number_sold) from purchases

$$

;

create function t()

returns table(msg varchar)

as

$$

select 'Hello'

union

select 'World'

$$;

select * from table(t());

create or replace function orders_for_product(prod_id varchar)

returns table (product_id varchar, quantitysold numeric(11, 2))

as

$$

select product_id, quantity from orders where product_id = prod_id

$$

;

select * from table(orders_for_product('GreenStar Helmet'));

create or replace function get_countries_for_user ( id number )

returns table (country_code char, country_name varchar)

as 'select distinct c.country_code, c.country_name

and c.country_code = a.country_code';