On Sun, Jan 10, 2010 at 8:06 PM, Dan Bishop <danbisho...@gmail.com> wrote: > Robert Citek wrote: >> Does anyone have any recommendations for books or other resources that >> deal with working with graphs (i.e. vertexes and edges) using sql? >> > I don't think that SQL is the best language for working with graphs, but: > > CREATE TABLE Graph ( > NodeFrom INTEGER, > NodeTo INTEGER > );
Yes, the Koenigsberg bridge problem is just one example of what I am referring to. I was working on creating a more general model initially with just two tables: one for vertexes and one for edges, which is a pairing of vertexes. For example: create table vertexes ( vertex integer ) ; create table edges ( v1 integer, v2 integer ) ; BEGIN; INSERT INTO vertexes VALUES (1); INSERT INTO vertexes VALUES (2); INSERT INTO vertexes VALUES (3); INSERT INTO vertexes VALUES (4); COMMIT; To create a complete graph: INSERT INTO edges SELECT v1.vertex, v2.vertex FROM vertexes v1 JOIN vertexes v2 WHERE v2.vertex > v1.vertex To generate the irreflexive symmetric relation on vertexes: CREATE VIEW isr AS SELECT v1.vertex, v2.vertex FROM vertexes v1 JOIN vertexes v2 WHERE v2.vertex != v1.vertex So, there seem to be ways of working with graphs within sql. I was just curious to know if there were texts that cover this subject. Joe Celko's books seem like one source. Are there others? As for SQL not being the best for working with graphs, I'm ok with that as I can use sqlite3 for storing and retrieving the graph data as well as some of the more simpler manipulations, and then use some other language for more sophisticated manipulations. Regards, - Robert _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
