I know there's the built-in _stats
function that gives you sum, count, min, max, and sumsqr.
What I'd like to know is how to calculate just the max in a map-reduce way. I can't come up with a reduce function that will work without some more information.
The only thing I can think of is to use sorting on the value and pick off the first value.
My map function looks like this:
function(doc){
emit(null, doc.value);
}