无法打印ajax成功函数数据

Question

I am creating a wordpress plugin that consist a form with Ajax Functionality.

I am able to see the json array as below in console tab while debugging.

Note: Error Function in Ajax Call displays below result:

Object {readyState: 4, responseText: "[{"id":"1","school_name":"Apollo Beach Elementary …lo Beach","rating":"A","type":"Elementary"}]Array", status: 200, statusText: "OK"}

Here is the Ajax Code

function ajaxformschool() {
        jQuery.ajax({
            url: ajaxschoolajax.ajaxurl,
            data: {'action':'ajaxschool_process'},
            dataType: 'json',
            type: "POST",
            success: function(data) {
                alert(data[0]);         
        },
     error:function(exception){console.log(exception);}
        });

}

Html link where the function is called

echo '<a onclick="ajaxformschool();" style="cursor: pointer"><b>Search</b></a>';    

Ajax Action Function

    function ajaxschool_process() {
    global $wpdb;
    $data = $wpdb->get_results ("SELECT * FROM schools;");

    echo json_encode($data);
    die($data);
}

Answer 1

Do not pass $data in die() function :

$data = $wpdb->get_results ("SELECT * FROM schools;");
echo json_encode($data);
die();

die() tries to print the value passed in parameter, then prints "Array", so jQuery can't parse the JSON data since it's not a valid JSON.