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| - | ====== Geographic Searches ====== | ||
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| - | [[admin:optimization:geo:home|Overview]] -> [[admin:optimization:geo:latlong|Latitude and Longitude]] -> [[admin:optimization:geo:radius|Radius Distance Searches]] -> [[admin:optimization:geo:indexing|Indexing]] -> **[[admin:optimization:geo:optimization|Optimization]]** | ||
| - | |||
| - | ===== Optimizing Geographic Searches ===== | ||
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| - | Geographic searches are specified using a [[dev:sql:functions:distance|$DISTANCE function]]. As long as there is a multi-column Omnidex index containing the latitude and longitude, the $distance function will be automatically optimized. | ||
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| - | ===== Examples ===== | ||
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| - | The following are examples of several types of geographic searches that can be optimized using the $distance function. | ||
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| - | ==== Example 1: Distance between two sets of coordinates ==== | ||
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| - | <code> | ||
| - | select $distance(40.0, -105.0, 41.0, -106.0) distance | ||
| - | from $omnidex; | ||
| - | |||
| - | </code> | ||
| - | |||
| - | ==== Example 2: Distance between two sets of coordinates using columns ==== | ||
| - | |||
| - | <code> | ||
| - | select zip, | ||
| - | $distance(40.0, -105.0, latitude, longitude) distance, | ||
| - | latitude, longitude, | ||
| - | from zipcodes | ||
| - | where $distance(40.0, -105.0, latitude, longitude) < 10; | ||
| - | |||
| - | </code> | ||
| - | |||
| - | ==== Example 3: Distance between an origin and multiple sets of destination coordinates ==== | ||
| - | |||
| - | <code> | ||
| - | select state, zip, latitude, longitude | ||
| - | from zipcodes | ||
| - | where $distance(latitude, longitude, | ||
| - | (select latitude, longitude | ||
| - | from zipcodes | ||
| - | where state = 'CO')) < 5; | ||
| - | </code> | ||
| - | |||
| - | **[[admin:optimization:geo:indexing|Prev]] ** | ||
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| - | ====== Additional Resources ====== | ||
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| - | * [[admin:optimization:home|Optimization Strategies]] | ||
| - | * [[admin:optimization:geo:math|The Math Behind Geographic Searches]] | ||
| - | * [[dev:sql:functions:distance|$DISTANCE function]] | ||
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