elasticsearch: Percolator. Another fascinating elasticsearch feature: Percolator lets you register searches with your elasticsearch cluster, then pass in a document and have the matching query IDs returned. It’s an upside down search engine. I’m sure there are some very neat things you could build with this, I just haven’t figured out what they are just yet.
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One use would be for a "search alerts" system. I could see letting users construct queries that are saved so that when a matching document appears (at a later time) you can notify the user that something they were looking for now exists.
Any time there is a live stream of data where a query at any point in time is necessarily incomplete, this reverse search is useful.
Jeremy Dunck - 9th February 2011 23:22 - #
This is the ballpark for Complex Event Processing, too, by the way.
Jeremy Dunck - 9th February 2011 23:26 - #
Shay summarizes what he thinks this would be useful for on the mailing list here - http://goo.gl/HyLhU
"This can be the basis for an event based systems, where after an index operation, the matches can then be distributed to interested parties.
Events being sent directly from ES for percolated index operations (with rabbitmq, webhooks, or something similar) to registered interested parties is down the road (not sure for 0.15)."
...so things involving subscribing or pushing.
Also be useful for building facets in real time for a collection of documents as you index them, although you'd need to do the counting yourself.
In terms of Twitter, would also be possible to define "trending" as the intersection between recent popular hash tags and recent popular searches.
Harry Fuecks - 13th February 2011 22:54 - #
flapwer - 27th October 2011 14:16 - #
Groundless - 1st November 2011 05:56 - #
BcRpB5 Good! Wish everybody wrote so:DD
Cheap software online - 7th November 2011 16:37 - #