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Alex Rivera
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I am looking for a CouchDB equivalent to "SQL joins". In my example there are CouchDB documents that are list elements: { "type" : "el", "id" : "1", "content" : "first" } { "type" : "el", "id" : "2", "content" : "second" } { "type" : "el", "id" : "3", "content" : "third" } There is one document that defines the list: { "type" : "list", "elements" : ["2","1"] , "id" : "abc123" } As you can see the third element was deleted, it is no longer part of the list. So it must not be part of the result. Now I want a view that returns the content elements including the right order. The result could be: { "content" : ["second", "first"] } In this case the order of the elements is already as it should be. Another possible result: { "content" : [{"content" : "first", "order" : 2},{"content" : "second", "order" : 1}] } I started writing the map function: map = function (doc) { if (doc.type === 'el') { emit(doc.id, {"content" : doc.content}); //emit the id and the content exit; } if (doc.type === 'list') { for ( var i=0, l=doc.elements.length; i<l; ++i ){ emit(doc.elements[i], { "order" : i }); //emit the id and the order } } } This is as far as I can get. Can you correct my mistakes and write a reduce function? Remember that the third document must not be part of the result. Of course you can write a different map function also. But the structure of the documents (one definig element document and an entry document for each entry) cannot be changed. EDIT: Do not miss JasonSmith's comment to his answer, where he describes how to do this shorter.
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