I have a situation where I want to run two different reduce functions on the output of a single map function. Like suppose I want one reduce function to get the count of all objects in each group (for example, documents with or without attachments), and another reduce to compute some other aggregate, like the average and standard deviation of a value, (like the average size of attached documents). (Yes, I know this is a stupid example, as the averaging reduce function will also have the count, but my real case is too complicated to write easily). Should one strive for a minimal set of reduce functions per map (one reduce for all three count, average, std deviation), or does it make sense to identically copy the maps and make multiple reduce functions (one reduce _each_ for count, mean, std dev)? (again, ignore the fact that you compute count and mean when computing std dev, etc) I have a feeling from reading the various docs that identical map functions are only executed once in CouchDB. If that is true, then is it _also_ true that having lots of reduce functions for one map is not any more expensive (in terms of space and computational speed) than trying for a minimal set of map-reduce pairs. Any advice on this? Thanks in advance, James -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.