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How can I ensure decimal precision in mongodb geospatial coordinates?

I need to store longitude / latitude coordinates in mongodb and I'm not sure how to store them. There are no examples where I see an online cast of converting to string or dividing decimal parts into 2 intervals. My guess is that in order to enable geo-indexing, I would have to store them as doubles, e.g .:

{ _id : 100, pos: { long : 126.9, lat : 35.2 }, type : "restaurant"}

I need at least 6 decimal places of precision, so how does this work in mongodb?

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MongoDB supportsdouble

data type. It is used for all floating point numbers. Since MongoDB implements the BSON specification, we can think of it as double BSON. This 8 bytes (64-bit IEEE 754 floating point)

is according to the specification . And it supports 15-17 significant digits.



So don't worry.

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Geo index MongoDB uses geohash


... You can adjust the hash precision to 32 bits , which gives the equivalent of approximately 8 or 9 decimal places of precision. This way you will lose some precision from the pairs, but still a lot for your application.
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