MySQL (table)
id | url | lat | lng
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1 | x | 44.339565 | -101.337891
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2 | y | 4
You may be interested in checking out the following presentation:
The author describes how you can use the Haversine Formula in MySQL to order by proximity and limit your searches to a defined range. He also describes how to avoid a full table scan for such queries, using traditional indexes on the latitude and longitude columns.
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