Does something as simple as this work?
map:
// This assumes "a" is in a doc field called key and "one" is in a
field called value
function(doc) {
emit(doc.key, doc.value);
}
reduce:
function(keys, values, rereduce) {
// rereduce and regular reduce are the
// same code here since they both just operate
// on the values array and return an array
var uniques = [];
for (var i = 0; i < values.length; i++) {
if (uniques.indexOf(values[i]) < 0) {
uniques.push(values[i]);
}
}
return uniques;
}
We just construct an array of unique values in the reduce. My simple
testing shows this returns reduce values like
{"rows":[{"key":"a","value":["two","one"]},{"key":"b","value":["three"]}]}
for map values of
{"total_rows":6,"offset":0,"rows":[
{"id":"34ab35d58a1540a24cea02aa6b97d2a6","key":"a","value":"one"},
{"id":"41099d0591233670250ebf146983cade","key":"a","value":"one"},
{"id":"70bd1f511ede201d93655f896ad4c99f","key":"a","value":"one"},
{"id":"c65afdfddfb3ea6a33cfd20e67364d11","key":"a","value":"two"},
{"id":"3b06e1ee7e63cd856aae52513f11bc51","key":"b","value":"three"},
{"id":"611a47c396492eb7b88190e81836427b","key":"b","value":"three"}
]}
