gps - How to calculate distances between coordinates EFFICIENTLY in Oracle -

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I have a large Oracle database (720,000 record epox) where each record has its own geographic coordinates (latitude and LNG) and I need to record only one record (within a specific radius) in a specific distance.

At this time I have implemented a distance function (based on Haverstein) which I have found in the Oracle forum but because the database is slightly larger, it spends about 50 seconds per selection.

How to do any recommendation efficiently? I know that there is an extension called Oracle Spectral. Locator but I do not know whether I can buy it or even how it works. Thank you very much in advance. Best Relationship

Use better algorithms Instead of computing the actual Euclidean distance, Calculation is required, make your selection at linear distance, for which only subtraction and addition is required. To wit. If you have talk (10, 10) and your radius is 5, then select all the locations (10 +/- 5, 10 +/- 5) inside the square created. Points will be

This will be done by calculating a small number of false positive in the corners of the square by judging the appropriate Euclidean distance and dual checking results in your application.


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