Javascript only producing last value of json encoded array - php

Question

here's the PHP/PDO.
try {
$query = 'SELECT Date,Close FROM DY_AAPL LIMIT 5';
$sth = $db->prepare($query);
$sth->execute();
while ($row = $sth->fetch(PDO::FETCH_ASSOC)){
$result_array=array();
$result_array[]=$row['Close'];
/* $num = $row['Close']; */
echo json_encode($result_array);
}
}catch (PDOException $e){
echo 'ERROR ' . $e->getMessage();
}
When I attempt to access the array using javascript, it's only outputting the last value in the array. Any pointers?
<script type="text/javascript">
var myjson = JSON.parse('<?php echo json_encode($result_array); ?>');
document.write(myjson);
</script>
I thought it might have something to do with 'JSON.parse,' but I'm not sure. Thanks in advance!

Answer 1

Try
$result_array = array();
while ($row = $sth->fetch(PDO::FETCH_ASSOC)) {
$result_array[]=$row['Close'];
/* $num = $row['Close']; */
}
echo json_encode($result_array);
…instead of initializing and outputting the array in each loop turn.

Answer 2

You should echo your end result, not every iteration:
while ($row = $sth->fetch(PDO::FETCH_ASSOC)){
$result_array=array();
$result_array[]=$row['Close'];
}
echo json_encode($result_array);

Answer 3

Try this for your PHP:
try {
$query = 'SELECT Date,Close FROM DY_AAPL LIMIT 5';
$sth = $db->prepare($query);
$sth->execute();
$result_array=array();
while ($row = $sth->fetch(PDO::FETCH_ASSOC)){
$result_array[]=$row['Close'];
}
echo json_encode($result_array);
}catch (PDOException $e){
echo 'ERROR ' . $e->getMessage();
}

Answer 4

It's because your doing the json encode within the while-loop. Place it outside the loop so the entire array get encoded.
Also, you're initializing the array within the while-loop. Which means that it will overwrite itself each time it loops.