I really appreciate your help, the truth is that the information you give me is quite useful. Finally I would like to ask you something. In my case I am doing a migration from mysql to arangodb and I worked the relationship one to one in the way you mentioned and from many to many creating an edge, however in the relational model I have a table that has more than two relationships many to many and in that case I don't know how to work it because creating an edge type document only allows me to create _from and _to and I don't know how I could work that situation. Could you give me some idea of it. I would appreciate you infinitely.
El miércoles, 26 de agosto de 2020 a las 16:30:40 UTC-5, [email protected] escribió: > ArangoDB does not require that you use graph methods in your query, nor > does it really penalize you if you choose not to. It is possible to keep a > "primary key" and/or "foreign key" attribute in each document (as is done > with normalized SQL tables) and use the FOR ... IN ... FILTER mechanism to > "join" collections - no edges required (just be sure you have indexes - use > explain > <https://www.arangodb.com/docs/3.7/aql/execution-and-performance-explaining-queries.html> > > to see if they're being used!). There are performance gains to be had when > using graphs because there are some optimizations built into the engine, > but they may be minor enough that you can forge ahead without. > > To use edges instead of "joins," you will have to create individual edge > documents for each relation. Obviously, this would be ridiculous to do by > hand, so scripting is necessary prior to or after import. Just iterate > over each document in collection A, find a match in collection B, then > insert an edge with those from/to attributes. Also, I recommend defining a > named > graph <https://www.arangodb.com/docs/3.7/graphs.html#named-graphs> so the > engine knows that edge collection C contains edges that go from collection > A to collection B. You can also use an anonymous graph > <https://www.arangodb.com/docs/3.7/graphs.html#anonymous-graphs> if you > want to sacrifice integrity and flexibility for some speed. > > On Wed, Aug 26, 2020 at 9:36 AM Marcela Guerrero <[email protected]> > wrote: > >> It happens that I am doing a migration process from Mysql to ArangoDB for >> academic reasons. Against this, in reading I have found that ArangoDb is >> quite flexible. However, I have doubts about passing the data from my >> tables to documents, mainly when I come from a schema with one-to-many and >> many-to-many relationships. >> I found that for one to many you can work directly in this way >> https://www.arangodb.com/docs/stable/aql/examples-join.html However, it >> is not clear to me how to work many to many if I must necessarily work it >> as edges or documents >> >> El miércoles, 26 de agosto de 2020 a las 11:21:43 UTC-5, >> [email protected] escribió: >> >>> Edges can only be one-to-one, and are directional (to/from). But that >>> doesn’t mean you can’t create lots of edges that connect a single node to >>> many others. >>> >>> The challenge is not in creating the relationships, but in how you >>> query. Making sure you are not creating loops, or more specifically, loops >>> that leads to loops. This would increase traversal complexity by orders of >>> magnitude, rendering even simple queries impossible. >>> >>> There are options to ensure a path is only traversed once, but those are >>> really for handling special cases, not every-day queries. It is MUCH more >>> important to model your data appropriately. >>> >>> Having lots of edges is not a problem - a poor data model *is* (and >>> missing indexes, too). >>> >>> — Kerry >>> >>> On Wed, Aug 26, 2020 at 9:07 AM Marcela Guerrero <[email protected]> >>> wrote: >>> >>>> Can edges only be used for the graph data model? Or I can use it >>>> similarly as if it were a many-to-many relationship in the relational >>>> model. >>>> What happens to many-to-many relationships in ArangoDB in the event >>>> that there are more than two involved tables as evidenced in a relational >>>> model ? >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> -- >>>> >>>> >>>> You received this message because you are subscribed to the Google >>>> Groups "ArangoDB" group. >>>> >>>> >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> >>>> >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/arangodb/6bfb59ce-375a-441e-8521-53688f879effn%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/arangodb/6bfb59ce-375a-441e-8521-53688f879effn%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>>> >>>> -- >> You received this message because you are subscribed to the Google Groups >> "ArangoDB" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/arangodb/1b0b0f78-263a-4caf-8c0a-de69d8025888n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/arangodb/1b0b0f78-263a-4caf-8c0a-de69d8025888n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "ArangoDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/arangodb/5fbb2239-53f0-4c26-9a6d-3fe92f6c4af9n%40googlegroups.com.
