This gist contains the sample queries used in the LineGraph presentation: https://docs.google.com/presentation/d/1TTSvKvF-a6P1WD_Aezc541vUHsoCUAQXMOfnBX3orcU/edit

LineGraph.sql

DROP TABLE IF EXISTS edge_table;
CREATE TABLE edge_table (
	id BIGSERIAL,
	source BIGINT,
	target BIGINT,
	cost FLOAT,
	reverse_cost FLOAT
);

INSERT INTO edge_table (
	source, target,
	cost, reverse_cost) VALUES
(5, 6, 1, 1), (2, 5, 1, 1),
(3, 6, 1, -1), (3, 2, 1, -1);

SELECT * FROM pgr_lineGraph (
	'SELECT id, source, target, cost, reverse_cost FROM edge_table');
  
/*************OUTPUT**********************************
 seq | source | target | cost | reverse_cost 
-----+--------+--------+------+--------------
   1 |      2 |      1 |    1 |           1
   2 |      3 |     -1 |    1 |          -1
   3 |      4 |      2 |    1 |          -1
(3 rows)
*************************************/