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#Geo Library for Amazon DynamoDB This project is an unofficial port of awslabs/dynamodb-geo, bringing creation and querying of geospatial data to Node JS developers using Amazon DynamoDB.

##Features

• Box Queries: Return all of the items that fall within a pair of geo points that define a rectangle as projected onto a sphere.
• Radius Queries: Return all of the items that are within a given radius of a geo point.
• Basic CRUD Operations: Create, retrieve, update, and delete geospatial data items.
• Customizable: Access to raw request and result objects from the AWS SDK for javascript.
• Fully Typed: This port is written in typescript and declaration files are bundled into releases.

##Limitations

###No composite key support Currently, the library does not support composite keys. You may want to add tags such as restaurant, bar, and coffee shop, and search locations of a specific category; however, it is currently not possible. You need to create a table for each tag and store the items separately.

###Queries retrieve all paginated data Although low level DynamoDB Query requests return paginated results, this library automatically pages through the entire result set. When querying a large area with many points, a lot of Read Capacity Units may be consumed.

###More Read Capacity Units The library retrieves candidate Geo points from the cells that intersect the requested bounds. The library then post-processes the candidate data, filtering out the specific points that are outside the requested bounds. Therefore, the consumed Read Capacity Units will be higher than the final results dataset.

###High memory consumption Because all paginated Query results are loaded into memory and processed, it may consume substantial amounts of memory for large datasets.

###The server is essential Because Geo Library calls multiple DynamoDB Query requests and processes the results in memory, it is not suitable for mobile device use. You should maintain a Java server, and use the library on the server.

###Dataset density limitation The Geohash used in this library is roughly centimeter precision. Therefore, the library is not suitable if your dataset has much higher density.