pg_rational

pig build pkg pg_rational;		# build rpm

pig repo add pgsql -u   # add both repo and update cache

pig install pg_rational;		# install via package name, for the active PG version

pig install pg_rational -v 18;   # install for PG 18
pig install pg_rational -v 17;   # install for PG 17
pig install pg_rational -v 16;   # install for PG 16
pig install pg_rational -v 15;   # install for PG 15
pig install pg_rational -v 14;   # install for PG 14

CREATE EXTENSION pg_rational;

CREATE EXTENSION pg_rational;

SELECT '1/3'::rational + '2/7'::rational;  -- 13/21
SELECT '3/4'::rational * '2/3'::rational;  -- 1/2

-- Simplify fractions
SELECT rational_simplify('36/12');  -- 3/1

-- Find intermediate fraction (Stern-Brocot tree)
SELECT rational_intermediate('1/2', '2/3');  -- 3/5

SELECT 0.263157894737::float::rational;  -- 5/19
SELECT '-1/2'::rational::float;          -- -0.5
SELECT 1::rational;                       -- 1/1

CREATE TABLE todos (
    prio rational UNIQUE DEFAULT nextval('todos_seq')::integer,
    what text NOT NULL
);

-- Insert between items at priority 1 and 2
INSERT INTO todos VALUES (rational_intermediate('1', '2'), 'new task');
-- prio becomes 3/2, no other rows affected