map function for link-walking

Nicolas Fouché nicolas at
Sat Jul 10 16:45:09 EDT 2010

In the "one-to-very-many link associations" thread , Sean Cribbs talks
about a map function which does link-walking from links stored in
object contents.

"Another way to cope with large numbers of links is to
encapsulate them in the object itself, rather than in the headers.  This removes
the header-length/count limitation, but would require you to have a map function
that understands the internals of the object.  Also, you would need to deal with
the larger size of the object, which could potentially slow down your request."

Is there any chance someone shares the code of a map function doing
this (custom-)link-walking ?

The only example I found is in the "Practical Map-Reduce: Forwarding
and Collecting" blog article
It gatheres links from objects and call the "map" function on them.
So, as Sean says, a Link object has to be build to be able to call the
"map" function on it.

By the way, the result of the "map" function is cached like any
standard Map phase ?

It's the only step before we go with Riak in our project :)


More information about the riak-users mailing list