```
-- see https://learnsql.com/blog/get-to-know-the-power-of-sql-recursive-queries/
create table edges
(
fromNode integer not null,
toNode integer not null,
distance real not null default 1,
speed real not null default 1,
primary key (fromNode, toNode)
) without rowid;
insert into edges(fromNode, toNode, distance, speed) values
(1, 2, 100, 40),
(1, 3, 70, 50),
(2, 3, 20, 40),
(3, 2, 20, 40),
(3, 4, 40, 50),
(2, 5, 30, 50),
(4, 5, 20, 40),
(5, 6, 20, 20),
(4, 6, 80, 100);
.parameter init
.parameter set :start 1
.parameter set :end 6
.parameter set :maxHops 10
.parameter set :maxCost 10
.parameter set :maxDistance 250
with paths (startAt, endAt, visited, hops, pathDistance, pathCost)
as (
select :start as startAt,
:start as endAt,
'/' || :start || '/' as visited,
0 as hops,
0 as pathDistance,
0 as pathCost
union all
select startAt as startAt,
toNode as endAt,
visited || toNode || '/' as visited,
hops + 1 as hops,
pathDistance + distance as pathDistance,
pathCost + distance / speed as pathCost
from paths, edges
where fromNode == endAt
and instr(visited, '/' || toNode || '/') == 0
and instr(visited, '/' || :end || '/') == 0
and hops < :maxHops
and pathCost < :maxCost
and pathDistance < :maxDistance
order by pathCost
)
select startAt, endAt, visited, hops, pathDistance, pathCost
from paths
where startAt == :start
and endAt == :end
;
```
The ORDER BY in the recursive part selects which paths to open first.