There is some graph - represented as edges in some assoc.table, and
they having some associated item with them (e.g. weight or length).
Is it possible to calculate the overall lenght of path from node to
node (if there is a path at all) in SQL?
Finding if there is a path in the graph from node1 to node2, with max,
say, 2 hops will look like:
FROM node as node1, node as node2, node as node3
link as link1, link as link2
SELECT link1.length,
WHERE node1.id == link1.in AND node2.id == link1.out ##1 hop
OR node1.id == link1.in AND node2.id == link1.out
AND node2.id == link2.in AND node3.id == link2.out ##2 hops
but i dont see how to also sum the link.length. or should i use UNION
instead of OR?
This can be extended to any static number of hops... but is it
possible to be done for a dynamic (unknown) number?
ciao
svil
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