How to get php database values to javascript array -

hi here using jquery auto-complete plugin. have php retrieved database values want use values in autocomplete plugin. want php values javascript array. how can this?

$(function() {     var availabletags = [       "actionscript",       "applescript",       "asp",       "basic",       "c",       "c++",       "clojure",       "cobol",       "coldfusion",       "erlang",       "fortran",     ];     $( "#category" ).autocomplete({       source: availabletags     });   }); 

php:

<?php require_once "config.php"; $q = strtolower($_get["q"]); if (!$q) return; $sql = "select distinct(category) completer"; $rsd = mysql_query($sql); while($rs = mysql_fetch_array($rsd)) {     $fname = $rs['category'];     echo "$fname" } ?> 

js script :

$(function() {     $.ajax({         type : 'get',         url : 'urlofmyfile.php',         data : 'q='+q,         datatype : 'json',         success : function(availabletags){             $( "#category" ).autocomplete({               source: availabletags             });         }     });    }); 

$.ajax documentation : http://api.jquery.com/jquery.ajax/

php script :

  <?php require_once "config.php"; $q = strtolower($_get["q"]); if (!$q) return; $sql = "select distinct(category) completer"; $rsd = mysql_query($sql); while($rs = mysql_fetch_array($rsd)) {     $fname[] = $rs['category']; } print json_encode($fname); exit; ?> 

json_encode documentation : http://php.net/manual/en/function.json-encode.php