Basically, you will have to maintain more filters. Also Lucene supports up to certain amount of fields, it wasn't designed to handle unlimited number of them
-- Itamar Syn-Hershko http://code972.com | @synhershko <https://twitter.com/synhershko> Freelance Developer & Consultant Author of RavenDB in Action <http://manning.com/synhershko/> On Wed, Dec 10, 2014 at 10:35 AM, Dror Atariah <dror...@gmail.com> wrote: > @Itamar: Can you please elaborate on the matter? Why/how does the number > of fields relevant here? > > On Wednesday, December 10, 2014 4:26:16 PM UTC+1, Itamar Syn-Hershko wrote: >> >> Lucene / Elasticsearch is pretty much insignificant to this as long as >> you use filters. You should prefer not_analyzed fields with string values >> to represent those flags vs having dedicated boolean fields if you will >> have more than a few such flags. >> >> -- >> >> Itamar Syn-Hershko >> http://code972.com | @synhershko <https://twitter.com/synhershko> >> Freelance Developer & Consultant >> Author of RavenDB in Action <http://manning.com/synhershko/> >> >> On Wed, Dec 10, 2014 at 10:22 AM, Dror Atariah <dro...@gmail.com> wrote: >> >>> Assume that I want to be able to flag documents in an index according to >>> their attributes: isFoo and isBar [1]. As far as I understand, there are >>> two approaches: >>> >>> 1) Use dedicated fields for the flags: If the document is a Foo then add >>> a field named isFoo. Similarly, for isBar. >>> 2) Use a flags field that will be an array of strings. In this case, if >>> the document is Foo then "flags" will contain the string "isFoo". >>> >>> What are the pros and cons in terms of space and runtime complexities? >>> >>> Bear in mind the following queries examples: Consider the case where one >>> wants to check the attributes of the documents in the index. In particular, >>> if I want to find the documents that are either Foo *or* Bar I can either >>> (a) In case (1): Use a Boolean "should" filter the surrounds two >>> "exists"'s filters checking whether either isFoo or isBar exist. >>> (b) In case (2): Use a single "exists" filter that checks the existence >>> of the field "flags". >>> >>> A different case, is if I want to find the documents that are both Foo >>> *and* Bar: >>> (a) In case (1): Like before, replace the "should" with a "must". >>> (b) In case (2): Surround two "term"s filters with a "must" Boolean one. >>> >>> Lastly, finding the documents that are Foo but *not* Bar. >>> >>> In the bottom line, In case (1) all queries boil down to mixture of >>> Boolean, exists and missing filters. In case (2), one has to process the >>> strings in the array of strings named "flags". My intuition is that it is >>> faster to use method (1). In terms of space complexity I believe there is >>> no difference. >>> >>> I'm looking forward to your insights! >>> Dror >>> >>> [1]: Obviously, there could be way more flags... >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "elasticsearch" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to elasticsearc...@googlegroups.com. >>> To view this discussion on the web visit https://groups.google.com/d/ >>> msgid/elasticsearch/ef637057-4303-4c75-9bbf-ed72e0d4806b% >>> 40googlegroups.com >>> <https://groups.google.com/d/msgid/elasticsearch/ef637057-4303-4c75-9bbf-ed72e0d4806b%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "elasticsearch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to elasticsearch+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elasticsearch/c376b40d-1c46-43f5-952f-96ec01338788%40googlegroups.com > <https://groups.google.com/d/msgid/elasticsearch/c376b40d-1c46-43f5-952f-96ec01338788%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAHTr4Zv78zrf%3DBkiBr%2BB5k_tM0qOS5QEA83BQ2PD34WtoXt_HA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
