What is an efficient way to store georeferenced information for web services?

I am specifically thinking about Ovi Maps or any other similar georeferenced web service. What is an efficient way to partition data so to scale properly? How do these services store data so to reduce the effort necessary to lookup a street in a city of nation s开发者_如何学Gotarting from a pair of coordinates? How do they also store the "shape" of geographical entities? P.S: This was an interview question.

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OpenGIS is a good reference/standard for location based entities/services: http://www.opengeospatial.org/

MySQL, the commonly used RDBMS has some geospatial support. http://dev.mysql.com/doc/refman/5.5/en/spatial-extensions.html

I don't have experience of sharding/partitioning data like this but guess you could do so by country or by creating "tiles".