Postgres 12

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CREATE TABLE network (
  id integer PRIMARY KEY,
  from_segment text,
  to_segment text, 
  from_meter int,
  to_meter int,
  direction text
);

INSERT INTO network (id, from_segment, to_segment, from_meter, to_meter, direction) VALUES
  (1,'A', 'B', 0, 5,'X'),
  (2,'A', 'B', 0, 5,'Y'),
  (3,'A', 'B', 5,10,'X'),
  (4,'A', 'B', 5,10,'Y'),
  (5,'A', 'B',10,15,'X'),
  (6,'A', 'B',10,15,'Y'),
  (7,'A', 'B',15,20,'X'),
  (8,'A', 'B',15,20,'Y'),

(9,'B', 'C', 0, 5,'X'),
  (10,'B', 'C', 0, 5,'Y'),
  (11,'B', 'C', 5,10,'X'),
  (12,'B', 'C', 5,10,'Y'),
  (13,'B', 'C',10,15,'X'),
  (14,'B', 'C',10,15,'Y'),
  (15,'B', 'C',15,20,'X'),
  (16,'B', 'C',15,20,'Y'),

(17,'C', 'D', 0, 5,'X'),
  (18,'C', 'D', 0, 5,'Y'),
  (19,'C', 'D', 5,10,'X'),
  (20,'C', 'D', 5,10,'Y'),
  (21,'C', 'D',10,15,'X'),
  (22,'C', 'D',10,15,'Y'),

(23,'E', 'F', 0, 5,'X'),
  (24,'E', 'F', 0, 5,'Y'),
  (25,'E', 'F', 5,10,'X'),
  (26,'E', 'F', 5,10,'Y'),

(27,'K', 'L', 0, 5,'X'),
  (28,'K', 'L', 0, 5,'Y'),
  (29,'K', 'L', 5,10,'X'),
  (30,'K', 'L', 5,10,'Y'),
  (31,'K', 'L',10,15,'X'),
  (32,'K', 'L',10,15,'Y'),

(33,'L', 'M', 0, 5,'X'),
  (34,'L', 'M', 0, 5,'Y');

34 rows affected

from_segment	to_segment	result_1	result_2
A	B	1	1
B	C	1	2
C	D	1	3
E	F	2	1
K	L	3	1
L	M	3	2