Getting Data from PHP, JSON Highcharts? - php

Question

Hi I am trying to get data from MySql table and show the data in Highcharts by using PHP and Json
I have try the example from internet and it is working fine but when I try to get data from my file it show nothing.
What I am trying to do:
I am creating table of office attendance system and trying to show record day by day. So at y axis I want to count names of employees and x axis the date of attendance.
Problem: Nothing Is show from mu json.
Here is what my Json looks like:
[["Hamza","07\/04\/2014"],
["Junaid","07\/04\/2014"],
["Usman","07\/04\/2014"],
["Rajab","07\/04\/2014"],
["Hamza","08\/04\/2014"],
["Junaid","08\/04\/2014"],
["Usman","08\/04\/2014"],
["Rajab","08\/04\/2014"]]
I am having to value names and dates.
My PHP which is creating my Json code:
// Set the JSON header
header("Content-type: text/json");
$result = mysqli_query($con,"SELECT * FROM attendence");
$a=array();
while($row = mysqli_fetch_array($result)) {
$row['name'] . "\t" . $row['date']. "\n";
$b=array();
array_push($b,$row['name']);
array_push($b,$row['date']);
array_push($a,$b);
}
echo json_encode($a);
and this is my Jquery code:
$(function() {
$.getJSON('highchart.php', function(data) {
// Create the chart
$('#chart').highcharts('StockChart', {
rangeSelector : {
selected : 1,
inputEnabled: $('#chart').width() > 480
},
title : {
text : 'Attendence'
},
series : [{
name : 'Empolyees',
data : data,
tooltip: {
valueDecimals: 2
}
}]
});
});
});

Answer 1

In the json_encode() you need to use JSON_NUMERIC_CHECK flag to avoid use string in your JSON
In the highstock you need to have timestamps and value, not name and date.
Dates should be timestamp, and as first element in array, not second as you have.

Answer 2

If you want to get a count of all people on a given day, you need to write a SQL query that returns that information. Assuming that date field is a datetime type and name is of varchar type:
SELECT COUNT(name) FROM attendence GROUP BY DATE(date);

Answer 3

perhaps you need to define what kind of data your x-axis will have
take a look at this fiddle (taken from highcharts website)
$(function () {
$('#container').highcharts({
xAxis: {
type: 'datetime'
},
series: [{
data: [
[Date.UTC(2010, 0, 1), 29.9],
[Date.UTC(2010, 2, 1), 71.5],
[Date.UTC(2010, 3, 1), 106.4]
]
}]
});
});