Re: Efficiently storing a directed graph - Mailing list pgsql-general

From Peter Brawley
Subject Re: Efficiently storing a directed graph
Date
Msg-id 47C9D8B2.9010901@earthlink.net
Whole thread Raw
In response to Efficiently storing a directed graph  ("Kelly Jones" <kelly.terry.jones@gmail.com>)
List pgsql-general
Kelly,

>I'm not married to using SQL: are there other efficient solutions to
>store directed graphs? Could I hack something up in Perl or Ruby and
>then serialize my in-memory graph to a file (for efficient
>saving/reloading)?

Did you look at Dijkstra's algorithm?

-----

Kelly Jones wrote:
> I have a directed graph (nodes and edges) that I want to store
> "efficiently": given two nodes, I want to quickly find the shortest
> path between them. The graph is NOT acyclic (it's not a tree), is
> fairly "sparse" (about 10000 edges for 2500 nodes), and changes
> occasionally.
>
> I know PostgreSQL/MySQL can store graphs (as one table of nodes and
> one table of edges that reference the nodes), but I think finding the
> shortest path between two nodes is quite inefficient that way.
>
> I know PostgreSQL/MySQL have special "plugins" (like PostGIS for
> PostgreSQL) for specific problems. Is there a directed graph plugin?
>
> I'm not married to using SQL: are there other efficient solutions to
> store directed graphs? Could I hack something up in Perl or Ruby and
> then serialize my in-memory graph to a file (for efficient
> saving/reloading)?
>
> As a minor note, the nodes/edges will have (non-unique) names and
> descriptions, and I want the ability to do fulltext searching on these
> names/descriptions. However, this is less important than quickly
> finding the shortest path between two nodes.
>
> --
> We're just a Bunch Of Regular Guys, a collective group that's trying
> to understand and assimilate technology. We feel that resistance to
> new ideas and technology is unwise and ultimately futile.
>
>

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