Incorrect results

For a query showing all possible destinations:

select g.*,a.text from graph g join atom a on a.id=g.linkid where g.latch='dijkstras' and g.origid=27;

+-----------+--------+--------+--------+------+--------+--------+
| latch | origid | destid | weight | seq | linkid | text |
+-----------+--------+--------+--------+------+--------+--------+
| dijkstras | 27 | NULL | 2 | 3 | 183 | rubber |
| dijkstras | 27 | NULL | 1 | 2 | 116 | tyres |
| dijkstras | 27 | NULL | 0 | 1 | 27 | wheels |
+-----------+--------+--------+--------+------+--------+--------+

Then querying for the path between 27 and 183:

select g.*,a.text from graph g join atom a on a.id=g.linkid where g.latch='dijkstras' and g.origid=27 and g.destid=183;
Empty set (0.00 sec)

No results.

Query cache disabled, restarted database, same problem.