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rch

This is exciting: db.users.mapReduce(map, reduce, {out: { inline : 1}});

This is Not exciting:

"Note that this option is possible only when the result set fits within the 16MB limit of a single document."

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I did a writeup, for what it's worth, on the new MapReduce output options:

http://blog.evilmonkeylabs.com/2011/01/27/MongoDB-1_8-MapRed...

(Disclaimer, I work for 10gen / MongoDB)

Very nice - worth the reading. I'm particularly interested in seeing how you've implemented 'merge' and 'reduce' output.

You guys do seem to be headed in the right direction technically... I just can't bring myself to say "mongo" out loud.

Not really a big deal to just output to a new collection and query that.

Sure - I'm just pointing out something that could be a big deal (streaming results through an ordered structure in memory, that may or may not be backed by a lazy disk store) is actually not a big deal, due to a current implementation constraint.

But you're right too, of course.

Yea, makes sense. That limit almost seems to fall along the lines of "Nobody should need more than 16MB for inline map/reduce results." ;)

cheers to that.

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