google app engine - Datastore - select nearby posts using given co-ordinates -


I use App Engine Datastore with JDO to store data about all users' posts with Latitude ; The longitude of the place from which they have been posted.

With the current user's co-ordination, I want to get the adjacent post within the current X's X-km user.

At first I tried to ask a question for a range of latitude; Longitude, but this is not possible because the datastore does not support inequality filters on many properties.

According to RDBMS, it can be achieved only by calculating within the query.

How can I do this query in JDO? Is the place a better way to store data, where can calculate distance and get it easily? 1 - High performance on large datasets is a good solution for geospatial detection.

Below, you have to duplicate your search index data in GAE-Search.

The best way to use this is to use the datastore key with the datastore in the form of DAC-ID in the GAE-Search index where you have one-to-one mapping with the datastore unit (and Use the same key in the candy cache which is the facility of NNDB / Object etc.) Then come back from GAE-Search to bring the document-id from Memphor.

2 - The most convenient way. If you need a geographic search then it will work as it does not require combination with a condition and ranking or full text search. And if the data is not expected to grow so big that you see performance problems.


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