Hi Everyone,
Thank you for your suggestions, based on that I was able to move forward.
I am now generating a Geohash for all the lats and lons in our reference
data and then creating a trie of all the Geohash's
I am then broadcasting that trie and then using it to search the nearest
Geohash for
Ted Dunning and Ellen Friedman's Time Series Databases has a section on
this with some approaches to geo-encoding:
https://www.mapr.com/time-series-databases-new-ways-store-and-access-data
http://info.mapr.com/rs/mapr/images/Time_Series_Databases.pdf
On Tue, Mar 10, 2015 at 3:53 PM, John Meehan
Thank you everyone!! I have started implementing the join using the geohash
and using the first 4 alphabets of the HASH as the key.
Can I assign a Confidence factor in terms of distance based on number of
characters matching in the HASH code?
I will also look at the other options listed here.
There are few techniques currently available.
Geomesa which uses GeoHash also can be proved useful.(
https://github.com/locationtech/geomesa)
Other potential candidate is
https://github.com/Esri/gis-tools-for-hadoop especially
https://github.com/Esri/geometry-api-java for inner customization.
If
Are you using SparkSQL for the join? In that case I'm not quiet sure you
have a lot of options to join on the nearest co-ordinate. If you are using
the normal Spark code (by creating key-pair on lat,lon) you can apply
certain logic like trimming the lat,lon etc. If you want more specific
computing
There are some techniques you can use If you geohash
http://en.wikipedia.org/wiki/Geohash the lat-lngs. They will naturally be
sorted by proximity (with some edge cases so watch out). If you go the join
route, either by trimming the lat-lngs or geohashing them, you’re essentially
grouping
Hi,
I am trying to join data based on the latitude and longitude. I have
reference data which has city information with their latitude and longitude.
I have a data source with user information with their latitude and
longitude. I want to find the nearest city to the user's latitude and
