Google maps downloadUrl does not return 200 - postgresql

Question

My code is based on the example of google code:
https://developers.google.com/maps/articles/phpsqlinfo_v3
and was working fine.
I need to change a former 'gid' (Integer) field to 'id' (String) to get saved to the database and used to display a new labeled symbol on the map.
The strange thing is, that the url, that is build in the code to call the addrow.php file is OK. When I capture this string with alert(url), and I manually use this string, the new data is added to the database.
In my script, the call seems to fail (responseCode == 200 && data.length <=1), since no data is written to the database and the alert from the 'else-clause' is displayed as short pop-up.
Here's the code I use in my project (to save data from a form):
//save new marker to Postgis-database and add new markerwithlabel on the fly
function saveData(){
var gender = escape(document.getElementById("gender").value);
var hoehe = InZahl(document.getElementById("hoehe").value);
var breite = InZahl(document.getElementById("breite").value);
var id = escape(document.getElementById("id").value);
var vital = document.getElementById("vital").value;
var typ = document.getElementById("typ").value;
var ein_mehr = document.getElementById("ein_mehr").value;
var st_durchm = document.getElementById("st_durchm").value;
var frucht = document.getElementById("frucht").value;
var anmerk = document.getElementById("anmerk").value;
var latlng = marker.getPosition();
var url = "./mapdata/addrow.php?gender=" + gender +
"&hoehe=" + hoehe + "&lat=" + latlng.lat() + "&lng=" + latlng.lng() +
"&breite=" + breite + "&id=" + id + "&typ=" + typ + "&ein_mehr=" +ein_mehr + "&st_durchm=" + st_durchm +
"&frucht=" + frucht +
"&vital=" + vital + "&anmerk=" + anmerk;
downloadUrl(url, function (data, responseCode) {
if (responseCode == 200 && data.length <=1) {
infowindow.close();
marker.setDraggable(false);
marker.setIcon('./images/mm_purple.png');
marker.labelContent = id;
marker.setMap(map);
downloadUrl("./mapdata/getxml_get_last.php", function (data1) {
var xml = parseXml(data1);
var ms = xml.documentElement.getElementsByTagName("m");
var gid = ms[0].getAttribute("gid");
var html_n = "<div id='InfoWindow'><p style='font-weight:bold;'>" + id + "</p> \n\<p>Höhe:" + hoehe + " Breite: "+ breite +
"<br />\n\Typ: "+typ+" Stämme: "+ein_mehr+" St-Durchm: "+ st_durchm + "<br />\n\Vitalität: "+vital+" Fruchtbehang: "+frucht+
"<p/>\n\<p style='text-align:right;'><a href='sm_juniperus.php?operation=ssearch&ResetFilter=0&SearchField=gid&FilterType=%3D&FilterText="+ gid +
"' target='_blank'> Daten editieren </a></p></div>";
infowindow.setContent(html_n);
bindInfoWindow(marker, map, infowindow, html_n);
(function(i, marker, gid) {
var origIcon = marker.getIcon();
new LongPress(marker, 1000);
google.maps.event.addListener(marker, 'longpress', function(e) {
marker.setDraggable(true);
marker.setIcon(mmcross);
});
google.maps.event.addListener(marker, 'dragend', function(){
updatePosition(marker, gid);
marker.setIcon(origIcon);
});
})(i,marker,gid);
//add new marker to markerCluster-Array and to markerArray
markerCluster.addMarker(marker,false);
markerArray.push(marker);
i++;
}); // End add new marker
}
else {
alert("Your data couldn't be saved!");
}
}); // End downloadUrl
}; // END saveData()
As I said, my code worked fine, but after 3 evenings passed to solve this, I thought it would be time to ask for help.
If anybody has an idea, where the mistake lies, I would apreciate any hint.

Answer 1

Just to confirm, you're aware that you by doing
if (responseCode == 200 && data.length <=1) {
you are saying 'if the request is successful and the data it returns is only one character or below in length'? I am unsure if this is intended or not, because this way the code inside the if statement is only ran if the response is successful but contains only 1 or 0 characters.