Have 2 rows of a database display same point on Google Map

Question

I'm trying to have multiple values for profFName and profLName display on a map where a single point should display this value.

So, if I have (2) pID connected to the same marker... it should display the profFName and profLName on one point.

** Right now it is creating two markers at the exact same lat/longitude so it is plotting 3 points (as seen from the database) but it doesnt show (1) point if multiple professors exist at that location **

Javascript

    <script type="text/javascript">
    //<![CDATA[

    var iconBlue = new GIcon(); 
    iconBlue.image = 'http://labs.google.com/ridefinder/images/mm_20_blue.png';
    iconBlue.shadow = 'http://labs.google.com/ridefinder/images/mm_20_shadow.png';
    iconBlue.iconSize = new GSize(12, 20);
    iconBlue.shadowSize = new GSize(22, 20);
    iconBlue.iconAnchor = new GPoint(6, 20);
    iconBlue.infoWindowAnchor = new GPoint(5, 1);

    var iconRed = new GIcon(); 
    iconRed.image = 'http://labs.google.com/ridefinder/images/mm_20_red.png';
    iconRed.shadow = 'http://labs.google.com/ridefinder/images/mm_20_shadow.png';
    iconRed.iconSize = new GSize(12, 20);
    iconRed.shadowSize = new GSize(22, 20);
    iconRed.iconAnchor = new GPoint(6, 20);
    iconRed.infoWindowAnchor = new GPoint(5, 1);

    var customIcons = [];
    customIcons["restaurant"] = iconBlue;
    customIcons["bar"] = iconRed;

    function load() {
      if (GBrowserIsCompatible()) {
        var map = new GMap2(document.getElementById("map"));
        map.addControl(new GSmallMapControl());
        map.addControl(new GMapTypeControl());
        map.setCenter(new GLatLng(47.614495, -122.341861), 13);

        GDownloadUrl("phpsqlajax_genxml.php", function(data) {
          var xml = GXml.parse(data);
          var markers = xml.documentElement.getElementsByTagName("marker");
          for (var i = 0; i < markers.length; i++) {
            var name = markers[i].getAttribute("name");
            var address = markers[i].getAttribute("address");
            var profFName = markers[i].getAttribute("profFName");
             var profLName = markers[i].getAttribute("profLName");
            var type = markers[i].getAttribute("type");
            var point = new GLatLng(parseFloat(markers[i].getAttribute("lat")),
                                    parseFloat(markers[i].getAttribute("lng")));
            var marker = createMarker(point, name, address, profFName, profLName, type);
            map.addOverlay(marker);
          }
        });
      }
    }

    function createMarker(point, name, address, profFName, profLName, type) {
            var marker = new GMarker(point, customIcons[type]);
            var html = "<b>" + name + "</b> <br/>" + address + "<br><br>" + profFName + profLName;
            GEvent.addListener(marker, 'click', function() {
              marker.openInfoWindowHtml(html);
            });
              return marker;
    }
    //]]>
  </script>

  </head>

  <body onload="load()" onunload="GUnload()">
    <div id="map" style="width: 110 0px; height: 500px"></div>
  </body>

PHP

<?php
require("phpsqlajax_dbinfo.php");

function parseToXML($htmlStr) 
{ 
$xmlStr=str_replace('<','&lt;',$htmlStr); 
$xmlStr=str_replace('>','&gt;',$xmlStr); 
$xmlStr=str_replace('"','&quot;',$xmlStr); 
$xmlStr=str_replace("'",'&#39;',$xmlStr); 
$xmlStr=str_replace("&",'&amp;',$xmlStr); 
return $xmlStr; 
} 

// Opens a connection to a MySQL server
$connection=mysql_connect ($host, $username, $password);
if (!$connection) {
  die('Not connected : ' . mysql_error());
}

// Set the active MySQL database
$db_selected = mysql_select_db($database, $connection);
if (!$db_selected) {
  die ('Can\'t use db : ' . mysql_error());
}

// Select all the rows in the markers table
$query = "SELECT * FROM markers M, professor P
WHERE P.id = M.id;";
if($row = mysql_fetch_array($result)) {
    do {
        echo $row;
    } 
    while($row = mysql_fetch_array($result));
} else {
    die('No results.');
}

header("Content-type: text/xml");

// Start XML file, echo parent node
echo '<markers>';

// Iterate through the rows, printing XML nodes for each
while ($row = @mysql_fetch_assoc($result)){
  // ADD TO XML DOCUMENT NODE
  echo '<marker ';
  echo 'name="' . parseToXML($row['name']) . '" ';
  echo 'address="' . parseToXML($row['address']) . '" ';
  echo 'profFName="' . parseToXML($row['profFName']) . '" ';
  echo 'profLName="' . parseToXML($row['profLName']) . '" ';
  echo 'lat="' . $row['lat'] . '" ';
  echo 'lng="' . $row['lng'] . '" ';
  echo 'type="' . $row['type'] . '" ';
  echo '/>';
}

// End XML file
echo '</markers>';

?>

As an important aside, have you considered standardizing the addresses you have (adding postal codes, etc) and verifying they actually exist? — Matt, Feb 10 '12 at 20:02

score 0 · Accepted Answer · edited May 23 '17 at 12:30

Quick solutions:

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Have 2 rows of a database display same point on Google Map

1 Answers1