Find all Locations near to my gps Location

Actually i h开发者_StackOverflowave millions of records of people in my server database and i want to fetch data of those people who are 5 miles near to me(i mean a circle with 5 miles radius )...

i am sending this data to an iPhone through webservice...

Please tell me how to do this on my PHP server....

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Probably this can help you

Let for example you have input latitude and longitude 37 and -122 in degree. And you want to search for users within 25 miles from current given latitude and longitude.

SELECT item1, item2, 
    ( 3959 * acos( cos( radians(37) ) 
                   * cos( radians( lat ) ) 
                   * cos( radians( lng ) 
                       - radians(-122) ) 
                   + sin( radians(37) ) 
                   * sin( radians( lat ) ) 
                 )
   ) AS distance 
FROM geocodeTable 
HAVING distance < 25 
ORDER BY distance LIMIT 0 , 20;

If you want search distance in kms. Then replace 3959 with 6371 in above query.

Get nearest places on Google Maps, using MySQL spatial data

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With millions of people records in your server database (I hope you're adhering to data protection laws), then you'll need to reduce the workload of calculating all these distances; otherwise you need to do the calculation for every single one of those millions of records.

Use PHP to calculate a "bounding box", which can be used to select a subset of likely candidates from your millions of people records, then only calculate the distance for that subset of people records. See this article from the movable type website for example PHP code describing how to do this, and an excellent description of how the method actually works.