How to create GeoSpatial index in MongoDB using C++ -


in python/pymongo, creating geospatial index quite trivial: 

db.collection.create_index([("loc", geo2d)], min=-100, max=100)

after can insert data using "loc" field.

but in c++/mongocxx, after referring mongocxx document (http://mongodb.github.io/mongo-cxx-driver/mongocxx-v3/tutorial/) , geospatial docement, still cannot figure out how this.

could kindly show me how deal geospatial index in c++? in advance.

you can create geospatial index c++ driver in similar way python driver; main difference instead of passing minimum , maximum direct arguments create_index, they're instead set in options::index object passed create_index. here's short program creates index described above using c++ driver: 

#include <bsoncxx/builder/basic/document.hpp> #include <bsoncxx/builder/basic/kvp.hpp> #include <mongocxx/client.hpp> #include <mongocxx/instance.hpp> #include <mongocxx/options/index.hpp> #include <mongocxx/uri.hpp>  using namespace mongocxx; using bsoncxx::builder::basic::kvp;  int main() {     instance inst{};      client conn{uri{}};     auto coll = conn["db_name"]["coll_name"];      bsoncxx::builder::basic::document index_doc;     index_doc.append(kvp("loc", "2d"));      coll.create_index(         index_doc.extract(),         options::index{}             .twod_location_min(-100).twod_location_max(100));

}


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