从PHP获取数组到AJAX [重复]

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                        <a href="/questions/15658246/ajax-showing-retrieved-values-as-undefined" dir="ltr">AJAX showing retrieved values as undefined</a>
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                                (5 answers)
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            <div class="grid--cell mb0 mt8">Closed <span title="2013-03-27 17:15:34Z" class="relativetime">7 years ago</span>.</div>
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I want to retrieve a set of array from PHP to ajax. The code I have does not return anything back, could someone help me how to retrieve the value from PHP to ajax. If i dont create the array in the mysql_fetch it will retrieve the last value from the database and pass it to the ajax function. I want to get the whole values. How can i do this?

AJAX CODE:

<script>
  //Global Variables
  var channel;
 function overall(){
    $(".one").show();
    $(".two").hide();
    $(".three").hide();
    $(".four").hide();
    window['channel']="overall";
     $.ajax({
             type:"GET",
             url:"dash2.php",
             data:{channel:channel},
             dataType:'json',
             success:function(data){
                    console.log(data.a);
                    console.log(data.b);
                    console.log(data.c);
                    }
            });
    }
</script>

PHP CODE:

<?php
   error_reporting(0);
   $channel=$_GET['channel'];
    $host="192.168.0.29";
    $username="root";
    $password="root";
    $dbname="realcl";
  mysql_connect($host,$username,$password)
    OR DIE ('Unable to connect to database! Please try again later.');
    mysql_select_db($dbname);
    $query = 'select * from '.$channel;
    $masterresult = mysql_query($query);
    $success[];
    $timeout[];
    $fail[];

    while($row1 = mysql_fetch_array($masterresult))
    {
        $success[]=$row1[1];
        $timeout[]=$row1[2];
        $fail[]=$row1[3]; 
    }

    echo json_encode(array("a"=>$success,"b"=>$timeout,"c"=>$fail));
?>

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