An introduction to Spatial Mongo I gave at Open Cloud Conf. Look for the PDF that contains the SQL I used during the talk.

1. Get your Spatial on with
MongoDB in the Cloud
Steven Citron-Pousty
PaaS Dust Spreader, Red Hat
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2. Agenda
• Learn a little spatial
• Load some spatial data into MongoDB
• Do a query or two
• Show some server-side code using it
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3. Assumptions
1) You can use the command line
2) You are comfortable with MongoDB command line
3) Please ask questions
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4. What is OpenShift?
Red Hat's free, auto-scaling Platform as a Service (PaaS) for
applications in the cloud.
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5. Kind of like Amazon, right? Nope.
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6. What’s supported?
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7. Looks great, but what’s the catch?
• OpenShift is free-as-in-beer & free-as-in-freedom
• Three 1.5 GB RAM / 3 GB storage gears
• Need more resources, just ask!
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8. On to Spatial and MongoDB
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9. Spatial is fun!
The only spatial functionality MongoDB currently has is:
2) Near
3) Containment
All of it is laid out on one page:
http://www.mongodb.org/display/DOCS/Geospatial+Indexing
First link on a google search for “MongoDB spatial
indexing”
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10. Caveats
1. Assumes coordinates are between -180 and 180
2. Can handle any 2d coordinates
3. Has methods to handle curvature of the earth
(spherical)
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11. How to make it work
1) Put your coordinates into an arrary
{ loc : [ 50 , 30 ] } //SUGGESTED OPTION
{ loc : { x : 50 , y : 30 } }
{ loc : { foo : 50 , y : 30 } }
{ loc : { lon : 40.739037, lat: 73.992964 } }
6) Make a 2d index
db.places.ensureIndex( { loc : "2d" } )
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12. Demo
1. I have an app and a MongoDB instance running
2. Load some spatial data in JSON format
3. Make the 2d index
4. Do a bunch of command you would need in building
an app (except Deleting docs, because that is easy
cheezy)
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13. Conclusion
1. Spatial is easy and fun on MongoDB!
2. You can now build your own FourSquare or other
check-in application.
3. You can also build your own field data entry system.
4. You can build and deploy your application quickly
without having to think about infrastructure.
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