Hello guys,

I am trying to store documents with location in GeoJSON format


However, after data are persisted, in SOME cases order of these coordinates is not kept. The problem is, that I am creating geospatial "2dsphere" index on "location" field and if order is not preserved, I can't use geo queries at all :(.
From what I have read so far, mongo driver should keep order of items within array during persistence. Am I missing something or ?

Java code of GeoJSON object in my application:


Thanks in advance!

Hi, see this post: viewtopic.php?t=1043903

Wouldn't it be better to store the coordinates as longitude and latitude instead of a list?

Anyway, at the moment, if you want to be sure you need to use the OrderColumn annotation but this will change the underlying mapping.

I've created an issue for this problem an dyou will find all the details in the post I linked.

Thanks,
Davide

Thank you DavideD for quick response and sorry for creating duplicate thread. I had to miss that one :(!

Well, the main reason I store them as a collection is that I want to query them using geo functions (for example to find closest "documents" to specific point on Earth. So the query would be like).

I am quite new to Hibernate and MongoDB, so please feel free to correct me if there is a better way to do that.

No, I think that's the way you are supposed to work with coordinates in MongoDB.

The fact that you cannot rely on the order of arrays is a bug in OGM.

I'll try to fix for the next release.

Thanks for the feedback,
Davide

Thanks for the fix Davide!
Storing of arrays now works fine and it keeps the order of items.(5.1 CR 1) However I found out that when fetching data from database, sometimes order of items is not kept.

Can you show me an example of when the order is not kept, please?

It is the same use case as above. When I fetch locations from DB, longitude and latitude are sometimes in reversed order. I checked them directly in database using Robomongo and they are stored properly.

Hi, I'll have a look again.

If you could provide a testcase it would help me a lot, though.

Thanks