> However, I think the original question from > Behrad still stands, is it more efficient to emit multiple keys per > document, or create multiple views?
My own analysis was: when emting multiple keys per document, we have more index keys, i.e. a bigger tree. Call it M*N indexes where M is number of emits per document and N is number of docs emitted! Since querying a B+ tree is logaritmic to the number of indexes, we MAY compare Log(N) with Log(M*N) with base of tree block sizes! and Since M is not that big in real applications, I don't think emiting multiple keys per doc will give much more poor performance in quering the view in comparision to one emit per document. Take that In the later scenario we may want to call multiple views and merge the results! Another unclarified thing for me is the situation where we emit array keys (i.e. [key1, key2,...] ). I don't know about how that affects query time. Is the couch behavior like single value keys? I don't know about CouchDB implementation specifics such as determining block size,... So I'd like CouchDB men can clarify these situations. --Behrad
