我有一个有效的PHP函数，它接受纬度/经度坐标和距离（英里），然后在邮政编码/ lat-lon对（40,000+行）的MySQL表中逐行测试是否每个邮政编码/ lat -lon行是否在指定距离内。
我知道这种方法非常低效，我想在SQL查询中而不是PHP中进行所有三角函数和距离计算。有人可以帮我从这里出去吗？我觉得我已经尝试了一切，但我无法正确获取SQL查询。任何帮助将不胜感激！
现有的PHP函数：
function getZips($lat, $lon, $radius)
{
//MySQL bit
$zipQuery = mysql_query("SELECT * FROM zip_codes");
while ($row = mysql_fetch_assoc($zipQuery))
{
$lat2 = $row['latitude'];
$lon2 = $row['longitude'];
$distance = (3958*3.1415926*sqrt(($lat2-$lat)*($lat2-$lat) + cos($lat2/57.29578)*cos($lat/57.29578)*($lon2-$lon)*($lon2-$lon))/180);
if ($distance <= $radius)
{
$zip = $row['zip'];
echo "Zip in range: <b>" .$zip . "</b><br>";
}
}
}
答案 0 :(得分：3)
SELECT zipcode, ( 3959 * acos( cos( radians( {$coords['latitude']} ) ) * cos( radians( latitude ) ) * cos( radians( longitude ) - radians( {$coords['longitude']} ) ) + sin( radians( {$coords['latitude']} ) ) * sin( radians( latitude ) ) ) ) AS distance FROM logic_zipcodes HAVING distance <= {$radius} ORDER BY distance
不记得我原来在哪里，但我已经使用了很长时间。这是我的功能：
function zipsearch($start, $rad) {
// ITITIAL POINT
$result = mysql_query("SELECT latitude,longitude FROM logic_zipcodes WHERE zipcode='" . $start . "'");
while($row = mysql_fetch_array($result)) {
$coords = array('latitude' => $row['latitude'], 'longitude' => $row['longitude']);
}
//RADIUS
$radius = $rad;
// SQL FOR MILES
$sql = "SELECT zipcode, ( 3959 * acos( cos( radians( {$coords['latitude']} ) ) * cos( radians( latitude ) ) * cos( radians( longitude ) - radians( {$coords['longitude']} ) ) + sin( radians( {$coords['latitude']} ) ) * sin( radians( latitude ) ) ) ) AS distance FROM logic_zipcodes HAVING distance <= {$radius} ORDER BY distance";
// OUTPUT THE ZIPCODES AND DISTANCES
$query = mysql_query($sql);
$zips = array();
while($row = mysql_fetch_assoc($query)) {
$zips[] = $row['zipcode'];
}
return $zips;
}
function getZips($zip, $rad) {
$zipcode = qt($zip);
$andstatement = implode("','", zipsearch($zipcode, $rad));
return "AND zipcode in('" . $andstatement . "')";
}
答案 1 :(得分：0)
这是与lat和long链接的所有州/城市的列表。 https://stackoverflow.com/questions/14272153/where-can-i-find-a-table-of-usas-zipcodes-lat-and-lon/14272155#14272155
至于你的trig，在Mysql和PHP中的其他所有内容中执行：
<?php
/**
* @package zipcode
*/
class ZipCode
{
private $zip_code_id;
private $zip_code;
private $lat;
private $lon;
private $city;
private $county;
private $area_code;
private $time_zone;
private $state_prefix;
private $state_name;
public $mysql_table = 'zip_code';
public $mysql_conn = false;
private $mysql_row;
private $print_name;
private $location_type;
const UNIT_MILES = 1;
const UNIT_KILOMETERS = 2;
const MILES_TO_KILOMETERS = 1.609344;
const LOCATION_ZIP = 1;
const LOCATION_CITY_STATE = 2;
/**
* Constructor
*
* Instantiate a new ZipCode object by passing in a location. The location
* can be specified by a string containing a 5-digit zip code, city and
* state, or latitude and longitude.
*
* @param string
* @return ZipCode
*/
public function __construct($location)
{
if (is_array($location)) {
$this->setPropertiesFromArray($location);
$this->print_name = $this->zip_code;
$this->location_type = $this::LOCATION_ZIP;
} else {
$this->location_type = $this->locationType($location);
switch ($this->location_type) {
case ZipCode::LOCATION_ZIP:
$this->zip_code = $this->sanitizeZip($location);
$this->print_name = $this->zip_code;
break;
case ZipCode::LOCATION_CITY_STATE:
$a = $this->parseCityState($location);
$this->city = $a[0];
$this->state_prefix = $a[1];
$this->print_name = $this->city;
break;
default:
throw new Exception('Invalid location type for '.__CLASS__);
}
}
}
public function __toString()
{
return $this->print_name;
}
/**
* Calculate Distance using SQL
*
* Calculates the distance, in miles, to a specified location using MySQL
* math functions within the query.
*
* @access private
* @param string
* @return float
*/
private function calcDistanceSql($location)
{
$sql = 'SELECT 3956 * 2 * ATAN2(SQRT(POW(SIN((RADIANS(t2.lat) - '
.'RADIANS(t1.lat)) / 2), 2) + COS(RADIANS(t1.lat)) * '
.'COS(RADIANS(t2.lat)) * POW(SIN((RADIANS(t2.lon) - '
.'RADIANS(t1.lon)) / 2), 2)), '
.'SQRT(1 - POW(SIN((RADIANS(t2.lat) - RADIANS(t1.lat)) / 2), 2) + '
.'COS(RADIANS(t1.lat)) * COS(RADIANS(t2.lat)) * '
.'POW(SIN((RADIANS(t2.lon) - RADIANS(t1.lon)) / 2), 2))) '
.'AS "miles" '
."FROM {$this->mysql_table} t1 INNER JOIN {$this->mysql_table} t2 ";
switch ($this->location_type) {
case ZipCode::LOCATION_ZIP:
// note: zip code is sanitized in the constructor
$sql .= "WHERE t1.zip_code = '{$this->zip_code}' ";
break;
case ZipCode::LOCATION_CITY_STATE:
$city = @mysql_real_escape_string($this->city);
$state = @mysql_real_escape_string($this->state_prefix);
$sql .= "WHERE (t1.city = '$city' AND t1.state_prefix = '$state') AND t2.zip_code = '$zip_to'";
break;
default:
throw new Exception('Invalid location type for '.__CLASS__);
}
switch (ZipCode::locationType($location))
{
case ZipCode::LOCATION_ZIP:
$zip_to = $this->sanitizeZip($location);
$sql .= "AND t2.zip_code = '$zip_to'";
break;
case ZipCode::LOCATION_CITY_STATE:
$a = $this->parseCityState($location);
$city = @mysql_real_escape_string($a[0]);
$state = @mysql_real_escape_string($a[1]);
$sql .= "AND (t2.city = '$city' AND t2.state_prefix = '$state')";
break;
}
$r = @mysql_query($sql);
if (!$r) {
throw new Exception(mysql_error());
}
if (mysql_num_rows($r) == 0) {
throw new Exception("Record does not exist calculating distance between $zip_from and $zip_to");
}
$miles = mysql_result($r, 0);
mysql_free_result($r);
return $miles;
}
public function getAreaCode()
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
return $this->city;
}
public function getCity()
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
return $this->city;
}
public function getCounty()
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
return $this->county;
}
public function getStateName()
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
return $this->state_name;
}
public function getStatePrefix()
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
return $this->state_prefix;
}
public function getDbRow()
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
return $this->mysql_row;
}
/**
* Get Distance To Zip
*
* Gets the distance to another zip code. The distance can be obtained in
* either miles or kilometers.
*
* @param string
* @param integer
* @param integer
* @return float
*/
public function getDistanceTo($zip, $units=ZipCode::UNIT_MILES)
{
$miles = $this->calcDistanceSql($zip);
if ($units == ZipCode::UNIT_KILOMETERS) {
return $miles * ZipCode::MILES_TO_KILOMETERS;
} else {
return $miles;
}
}
public function getZipsInRange($range_from, $range_to, $units=1)
{
if (empty($this->zip_code_id)) $this->setPropertiesFromDb();
$sql = "SELECT 3956 * 2 * ATAN2(SQRT(POW(SIN((RADIANS({$this->lat}) - "
.'RADIANS(z.lat)) / 2), 2) + COS(RADIANS(z.lat)) * '
."COS(RADIANS({$this->lat})) * POW(SIN((RADIANS({$this->lon}) - "
."RADIANS(z.lon)) / 2), 2)), SQRT(1 - POW(SIN((RADIANS({$this->lat}) - "
."RADIANS(z.lat)) / 2), 2) + COS(RADIANS(z.lat)) * "
."COS(RADIANS({$this->lat})) * POW(SIN((RADIANS({$this->lon}) - "
."RADIANS(z.lon)) / 2), 2))) AS \"miles\", z.* FROM {$this->mysql_table} z "
."WHERE zip_code <> '{$this->zip_code}' "
."AND lat BETWEEN ROUND({$this->lat} - (25 / 69.172), 4) "
."AND ROUND({$this->lat} + (25 / 69.172), 4) "
."AND lon BETWEEN ROUND({$this->lon} - ABS(25 / COS({$this->lat}) * 69.172)) "
."AND ROUND({$this->lon} + ABS(25 / COS({$this->lat}) * 69.172)) "
."AND 3956 * 2 * ATAN2(SQRT(POW(SIN((RADIANS({$this->lat}) - "
."RADIANS(z.lat)) / 2), 2) + COS(RADIANS(z.lat)) * "
."COS(RADIANS({$this->lat})) * POW(SIN((RADIANS({$this->lon}) - "
."RADIANS(z.lon)) / 2), 2)), SQRT(1 - POW(SIN((RADIANS({$this->lat}) - "
."RADIANS(z.lat)) / 2), 2) + COS(RADIANS(z.lat)) * "
."COS(RADIANS({$this->lat})) * POW(SIN((RADIANS({$this->lon}) - "
."RADIANS(z.lon)) / 2), 2))) <= $range_to "
."AND 3956 * 2 * ATAN2(SQRT(POW(SIN((RADIANS({$this->lat}) - "
."RADIANS(z.lat)) / 2), 2) + COS(RADIANS(z.lat)) * "
."COS(RADIANS({$this->lat})) * POW(SIN((RADIANS({$this->lon}) - "
."RADIANS(z.lon)) / 2), 2)), SQRT(1 - POW(SIN((RADIANS({$this->lat}) - "
."RADIANS(z.lat)) / 2), 2) + COS(RADIANS(z.lat)) * "
."COS(RADIANS({$this->lat})) * POW(SIN((RADIANS({$this->lon}) - "
."RADIANS(z.lon)) / 2), 2))) >= $range_from "
."ORDER BY 1 ASC";
$r = mysql_query($sql);
if (!$r) {
throw new Exception(mysql_error());
}
$a = array();
while ($row = mysql_fetch_array($r, MYSQL_ASSOC))
{
// TODO: load ZipCode from array
$a[$row['miles']] = new ZipCode($row);
}
return $a;
}
private function hasDbConnection()
{
if ($this->mysql_conn) {
return mysql_ping($this->mysql_conn);
} else {
return mysql_ping();
}
}
private function locationType($location)
{
if (ZipCode::isValidZip($location)) {
return ZipCode::LOCATION_ZIP;
} elseif (ZipCode::isValidCityState($location)) {
return ZipCode::LOCATION_CITY_STATE;
} else {
return false;
}
}
static function isValidZip($zip)
{
return preg_match('/^[0-9]{5}/', $zip);
}
static function isValidCityState($location)
{
$words = split(',', $location);
if (empty($words) || count($words) != 2 || strlen(trim($words[1])) != 2) {
return false;
}
if (!is_numeric($words[0]) && !is_numeric($words[1])) {
return true;
}
return false;
}
static function parseCityState($location)
{
$words = split(',', $location);
if (empty($words) || count($words) != 2 || strlen(trim($words[1])) != 2) {
throw new Exception("Failed to parse city and state from string.");
}
$city = trim($words[0]);
$state = trim($words[1]);
return array($city, $state);
}
// @access protected
private function sanitizeZip($zip)
{
return preg_replace("/[^0-9]/", '', $zip);
}
private function setPropertiesFromArray($a)
{
if (!is_array($a)) {
throw new Exception("Argument is not an array");
}
foreach ($a as $key => $value)
{
$this->$key = $value;
}
$this->mysql_row = $a;
}
private function setPropertiesFromDb()
{
switch ($this->location_type) {
case ZipCode::LOCATION_ZIP:
$sql = "SELECT * FROM {$this->mysql_table} t "
."WHERE zip_code = '{$this->zip_code}' LIMIT 1";
break;
case ZipCode::LOCATION_CITY_STATE:
$sql = "SELECT * FROM {$this->mysql_table} t "
."WHERE city = '{$this->city}' "
."AND state_prefix = '{$this->state_prefix}' LIMIT 1";
break;
}
$r = mysql_query($sql);
$row = mysql_fetch_array($r, MYSQL_ASSOC);
mysql_free_result($r);
if (!$row)
{
throw new Exception("{$this->print_name} was not found in the database.");
}
$this->setPropertiesFromArray($row);
}
}
?>