I think that would require you to read the entire view every time, though.
On 16 October 2012 10:53, boazc <[email protected]> wrote: > Thanks Robert. > > It crossed my mind that I can use List function and expect say include-keys > and exclude-keys query parameters thus filter out the undesired documents. > 1. Do you think the performance of such function will be reasonable? > 2. Can I still support pagination through a List function? > > Cheers. > > On Tue, Oct 16, 2012 at 3:30 PM, Robert Newson-2 [via CouchDB Development] < > [email protected]> wrote: > >> I can't speak about ElasticSearch, but the CouchDB-Lucene query would >> certainly reflect the current state of your database (i.e, no "delay") >> when you query. >> >> As for the original question, I don't think you can achieve it >> directly with CouchDB views. If you emit each tag of a document as a >> key, and null for value (e.g, emit("a",null)), then you could make two >> concurrent queries for ?key=a and ?key=b, and read each, row by row, >> filtering out as appropriate. It's not trivial. >> >> B. >> >> On 16 October 2012 05:50, boazc <[hidden >> email]<http://user/SendEmail.jtp?type=node&node=7581300&i=0>> >> wrote: >> >> > Hello, >> > >> > My documents contain tags which have a corresponding view. >> > I want to retrieve all documents that contain a certain tag, but don't >> > contain another one. >> > (Note that I don't know about the possible tags in advance). >> > >> > Example: >> > id: doc1, tags: [a, b] >> > id: doc2, tags: [b, c] >> > id: doc3, tags: [a, c] >> > If I want all docs with tag=a but not tag=b I expect to get only doc3. >> > >> > Is there a way to achieve this on CouchDB side? >> > Needless to say I cannot do it on the client side as I cannot benefit >> from >> > pagination and anyway might receive an extreme set of documents I need >> to >> > work on. >> > >> > I know I can turn to some search engines e.g. ElasticSearch or >> > CouchDB-Lucene, but other than introducing a new component to the system >> it >> > also means an inherent delay between the "real" data and the indexed >> data >> > which in my domain is unacceptable. >> > >> > Thanks!! >> > >> > >> > >> > -- >> > View this message in context: >> http://couchdb-development.1959287.n2.nabble.com/Dynamically-excluding-documents-from-a-view-query-tp7581297.html >> > Sent from the CouchDB Development mailing list archive at Nabble.com. >> >> >> ------------------------------ >> If you reply to this email, your message will be added to the discussion >> below: >> >> http://couchdb-development.1959287.n2.nabble.com/Dynamically-excluding-documents-from-a-view-query-tp7581297p7581300.html >> To unsubscribe from (Dynamically) excluding documents from a view query, >> click >> here<http://couchdb-development.1959287.n2.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=7581297&code=YmNpdHJpbkBnbWFpbC5jb218NzU4MTI5N3wtMTkyNTAwODYwOA==> >> . >> NAML<http://couchdb-development.1959287.n2.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml> >> > > > > > -- > View this message in context: > http://couchdb-development.1959287.n2.nabble.com/Dynamically-excluding-documents-from-a-view-query-tp7581297p7581301.html > Sent from the CouchDB Development mailing list archive at Nabble.com.
