Elasticsearch equivalent to Map-Reduce -


what equivalent of map-reduce in elasticsearch when processing client-side? there "streaming" client can reduce data output comes in?

assume need join, or complex filtering @ client side, type might not fit in memory without map-reduce scheme. don't mind waiting long time response, dont want crush machine (client and/or server).

how should go this?

example, mappings:

{"book":{"properties":{                        "title":{"type":"string", "index":"analyzed"},                        "author":{"type":"string", "index":"analyzed"}, }  {"character":{"properties":{                        "book_id":{"type":"string", "index":"not_analyzed"},                        "name":{"type":"string", "index":"analyzed"},                        "age":{"type":"integer"},                        "catch-phrase":{"type":"string", "index":"analyzed"}, }

say want find books have @ least m characters have catch phrase no longer n (where n parameter supplied @ client side)

so get_books_with_short_phrases(m,n)

i of course add fields such "phrase-length" "character" type, let's assume processing on "catch-phrase" might changing time.

i'd stream "characters" , "books" client, go on each client , output key-value of <book>-<character,len(phrase)> reduce further <book>-<num_of_chars_with_short_phrase>

if load documents client memory, might disaster. if client processes each book , reduces k,v might better.

am going wrong it?

is solution running scripts on server somehow, performs map-reduce?

afaik can't streaming es.

as i'm sure know it's best different mindset in 'joins' not exist. instead denormalize , try cover usecase 1 query es of course doesn't work.

in above case however, invite take @ script-filter, allows complex computations (akin sql stored procedures) allow query-time parameters.

i'm pretty confident should give tools query in 1 go on server, although didn't deep it.

http://www.elasticsearch.org/guide/reference/query-dsl/script-filter/ http://www.elasticsearch.org/guide/reference/modules/scripting/


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