> Be aware of the 16MB-per-document limit -- if you have 3.5M integers in an
> array, each int will require a type header (1 byte), an index (about 8
> bytes, if your indexes are in the millions), and the int (4 bytes),
> resulting in around 16 bytes to store each int. So you can't store more
> than about 1M integers in a single document's array.
> Seehttp://bsonspec.org/#/specification

> This may be the reason for your "Assertion: 10263:unknown error reading
> file mongodb " message.

> How is your graph structured? Is it a tree, a directed acyclic graph, or
> can it be cyclic?

> On Wednesday, May 23, 2012 12:11:03 PM UTC-4, Nicolas wrote:

> > Hi everybody,

> >    We try to store a graph by using MongoDB.
> >    We want to store our graph as an adjacency list : each node has an
> > identifier and a list of nodes which he's linked to.
> >    { id : identifier_of_the_node,
> >     out : [ list_of_identifier_of_the_nodes_he_s_linkedto]
> >    }

> >    However, the link of nodes stored in the "out" field can be really
> > large : 500 000 nodes for example.
> >    Thus, we don't know how to load efficiently our graph into mongoDB.
> >    Using mongoimport allows us to load really fast our data (Json
> > format) but it seems not to work with large "out" array : User
> > Assertion: 10263:unknown error reading file mongodb
> >    And using the JAVA API, it's too slow...
> >    How can we do ?

> >    Moreover, if we want to add a field "in" in our object to know
> > which node are linked to the current node :
> >     { id : identifier_of_the_node,
> >     out : [ list_of_identifier_of_the_nodes_he_s_linkedto],
> >     in :
> > [ list_of_identifier_of_the_nodes_which_are_linked_to_this_one],
> >     }
> >    we may have 3,5millions of integer in the "in" array.
> >    Is it possible to store it in MongoDB ? I saw that we may use
> > GridFS for heavy documents... should we use it ? Can we do Map/reduce
> > on GridFsFile, can we query it easily and fastly ?

> > Thanks a lot