PHP讀取SQL查詢-選擇2個值-在特定的行值上運行一些數學運算將值添加到新列？

Question

問題：我調用了一個SQL查詢。 我希望能夠將其拉入數組（tbh我現在要這樣做），然后從每一行中拉出特定值，運行一些數學運算（我有此運算法則），然后將此數學運算的結果添加到位於查詢的結尾（或開頭），然后可以在同一數組或新數組上使用它。

這是要計算出構成SQL查詢一部分的當前位置，然后要計算出每個事件的距離（每行一個）。

SQL查詢->檢查事件位置->在當前位置上運行事件距離數學->重新編譯為（SQL查詢+距離）數組以准備JSON輸出。

我將添加我已經設法針對xml輸出執行此操作，但是在處理數組時我仍然是菜鳥。

謝謝

人族

    // Connect to database server   
$con = mysql_connect($config_databaseServer,$config_databaseUsername,$config_databasePassword) or die(mysql_error());
mysql_select_db($config_databaseName, $con);    

// Access tables    
$sql = "SELECT * FROM " . $config . " WHERE LAT <" . $toplat . " AND LAT > " . $bottomlat . " AND LONG > " . $leftlon . " AND LONG < " . $rightlon . " AND VALIDPERIOD_STARTOFPERIOD < '" . $nowtime . "' AND VALIDPERIOD_ENDOFPERIOD > '" . $nowtime ."')";

// Execute query
$result = mysql_query($sql) or die(mysql_error());

$lata = $latitude;
$lona = $longitude;
    // Need to populate these from each row values in the query
$latb = $sqllat;
$lonb = $sqllong;                   
// need to place this in to a colum at the end of each row
    $distancefromevent = coordDistance($lata, $longa, $latb, $lonb, "m");

    // need to reform all the above so I can carry on and use the code that follows


$responses = array();
if(mysql_num_rows($result)) {
  while($response = mysql_fetch_assoc($result)) {
    $responses[] = array('dataitem'=>array_map('utf8_encode',$response));
  }
}

header('Content-type: application/json');
$json = json_encode(array($config_datexdeftype=>$responses));

$callback = $_GET[callback];
echo $callback . '(' . $json . ')';

};

return TRUE;

Answer 1

是否要使用SQL查詢來計算位置（緯度經度）之間的距離？

如果是這樣，那就是這樣： https : //developers.google.com/maps/articles/phpsqlsearch?hl=hu-HU

Answer 2

這應該工作。

請注意，出於可讀性考慮，一些長代碼已替換為[...] 。

// Connect to database server   
$con = mysql_connect([...]) or die(mysql_error());
mysql_select_db($config_databaseName, $con);    

// Access tables    
$sql = "SELECT * FROM " . $config . " WHERE [...]";

// Execute query
$result = mysql_query($sql) or die(mysql_error());

// Prepare the loop
$lata = $latitude;
$lona = $longitude;
$responses = array();

// Loop over each records (stay correct even if there is no record)
while($response = mysql_fetch_assoc($result)) {
    // we assume that latitude and longitude are given by
    //  columns 'lat' and 'lon' in the SQL query.
    $latb = $response['lat']; 
    $lonb = $response['lon'];
    $distancefromevent = coordDistance($lata, $longa, $latb, $lonb, "m");
    $response['distance'] = $distancefromevent;
    $responses[] = array('dataitem'=>array_map('utf8_encode',$response));
}

header('Content-type: application/json');
$json = json_encode(array($config_datexdeftype=>$responses));

$callback = $_GET[callback];
echo $callback . '(' . $json . ')';

return TRUE;