Question

Following on from this thread: Accessing MySQL database – D3

Can anyone help with a parse error I’m getting? There seems to be conflicting information out there about what can cause this?

Parse error:

Error: Problem parsing d=”M30,NaNL34,NaNL38,NaNL42,NaNL46,NaNL50,NaNL54,NaNL58…….

getdata.php:

    <?php
    $username="*****"; 
    $password="*****";   
    $host="********";
    $link=mysql_connect($host,$username,$password)
    or die("Unable to connect to MySQL");

    mysql_select_db("*****", $link) or die( "Unable to select database"
    .mysql_error());

    $res = mysql_query("SELECT * FROM TestSourceSampleData")
    or die ("Unable to run query");
    $data = array();

    while ($row = mysql_fetch_assoc($res))
    {  
    $data[] = array("reading" => $row['reading']);
    } 
    echo json_encode($data);     
    mysql_close($link);
    ?>

Output from getdata.php:

[{“reading”:”10″},{“reading”:”10.2″},{“reading”:”10.3″},{“reading”:”10.3″}……..

..when print json file:

    Array[120]
    [0 … 99]
    0: Object
    reading: "10"
    __proto__: Object
    1: Object
    reading: "10.2"
    __proto__: Object
    2: Object
    reading: "10.3"
    __proto__: Object
    3: Object
    4: Object
    5: Object

http://bl.ocks.org/5fc4cd5f41a6ddf2df23

Answer 1

In your block you use:

var data = jsondata.map(function(d) { return d.Value; });

while in your question you mention that the name of the key is reading, which would mean your code should look like:

var data = jsondata.map(function(d) { return d.reading; });