Array of associated documents

[myobie]

In my project, I have a need for an embedded has_many_related. Yeah, I
know that's crazy.

Simplified, I need Book to be { "authors": [1,2,3] } where 1, 2, and 3
are _id's of Authors.

While I am looking into writing my own module to make this possible, I
was curious if anyone has done this before or if anyone has any ideas
of how best to achieve this?

[Durran Jordan]

Is authors stored in a relational database? As long as the authors table has a column for book_id that's a String, Mongoid's has_many_related would work out of the box for you... I'm not sure I understand the embedded part of what you're asking. Is author an embedded document in another collection in Mongo?

2010/1/11 myobie <myo...@gmail.com>

[Igor Gladkoborodov]

In MongoMapper you can store has_many association in array of ids:
many :authors, :in => :author_ids
many :books, :foreign_key => :author_ids

It would be great if we could do it in MongoID's has_many_related.

[Eric Falcao]

If you take a look at http://www.mongodb.org/display/DOCS/MongoDB+Data+Modeling+and+Rails
they use "voters" as an array of user_ids that have "upmoderated" a
story. I guess the idea is that it could be more efficient than
foreign keys on the other collection (depending on your usage....).

Thank you so much for mongoid. It is very exciting to see such a
fantastic library come along. Versioning is amazing!

-Eric

On Jan 12, 9:23 am, Igor Gladkoborodov <igor.gladkoboro...@gmail.com>
wrote:

[Kyle Banker]

Eric,

Also, storing voters as an array makes it possible to record an upvote using a single atomic update operation. See this newly added example:

http://www.mongodb.org/display/DOCS/MongoDB+Data+Modeling+and+Rails#MongoDBDataModelingandRails-AtomicUpdates

Kyle 

[Durran Jordan]

Looks like has_many_related gets some love tonight then. :)

2010/1/12 Eric Falcao <efa...@gmail.com>

[Thomas R. Koll]

On 13 Jan., 00:05, Durran Jordan <dur...@gmail.com> wrote:
> Looks like has_many_related gets some love tonight then. :)

Can you post a follow-up wether anything came out of this night full
with love?

ciao, tom