parse json array with javascript : I have a mySQL database with a table of Latitudes and longitudes with associated data. I'm trying to create a Google Map and want to parse the JSON string using Javascript. I have looked here and on youtube and I don't know how to solve what I'm doing wrong.
Here is my json string that I get with my echo statement:
{"cm_mapTABLE":[["1","Angels Rest Photos OR","Angels_Rest_Photos_OR","663","aaj.jpg","2","Angel's Rest","Hike one of the trails in the Gorge with a scenic overlook, stream, and waterfall.","0","blue","4.5","45.5603","-122.171","http:\/\/www.eyehike.com\/pgallery\/index.php?\/category\/6","Angels_Rest_Photos_OR\/aae.thumb.jpg\" ALIGN=left HEIGHT=115 WIDTH=150>","http:\/\/www.eyehike.com\/pgallery\/i.php?\/galleries\/Angels_Rest_Photos_OR\/aaj-th.jpg","","","",""],["2","Ape Canyon Photos WA","Ape_Canyon_Photos_WA","681","PICT0114.jpg","3","Ape Canyon Trail","This trail is popular with hikers and mountain bikers with great views of several mountains.","0","blue","11","46.1653","-122.092","http:\/\/www.eyehike.com\/pgallery\/index.php?\/category\/8","Ape_Canyon_Photos_WA\/PICT0114.thumb.jpg\" ALIGN=left HEIGHT=115 WIDTH=150>","http:\/\/www.eyehike.com\/pgallery\/i.php?\/galleries\/Ape_Canyon_Photos_WA\/PICT0114-th.jpg","","","",""]]} 

Here is my code:

    <!DOCTYPE html>
    <head>
    <?php
    require("phpsqlsearch_dbinfo.php"); // This is the file with your logon info
    
     //$host="localhost"; //replace with your hostname 
     //$username="root"; //replace with your username 
     //$password=""; //replace with your password 
     //$db_name="$database"; //replace with your database 
     $con=mysqli_connect("$hostname", "$username", "$password", "$database")or die("cannot connect"); 
     //mysqli_select_db("$db_name")or die("cannot select DB");
     $sql = "select * from location_markers WHERE mrk_id < 3"; //replace emp_info with your table name 
     $result = mysqli_query($con, $sql);
     $json_string_data = array();
     if(mysqli_num_rows($result)){
    	while($row=mysqli_fetch_row($result)){
    		$json_string_data['cm_mapTABLE'][]=$row;
    	}
     }
     mysqli_close($con);
     
     //	You have to give the json a name to make it accessible by JS, e.g.:
    //	echo 'file='.json_encode($json_string_data),';';
     
     // This statement will echo the json output in the displayed web page
     echo json_encode($json_string_data); 
     // please refer to our PHP JSON encode function tutorial for learning json_encode function in detail 
     ?>
     </head>
     <body>
    	<script>
    	for (i = 0;i < $json_string_data.length;i++){
    	var  javascript_string_data=<?php echo json_encode($json_string_data); ?>;
    		document.write(cm_mapTABLE.rank[i]);
    	}
    		</script>
     </body>
     </html>

I'm using Firebug and here is the error:
ReferenceError: $json_string_data is not defined
	
for (i = 0;i < $json_string_data.length;i++){

Could someone please tell me the proper way to refer to elements in my JSON string? Do I need to somehow get the field names in my JSON string?

