Input post not working onchage event CodeIgniter - php

Question

My $this->input->post is not working when I changed the value of a dropdown menu (it dynamically display the record from db) it does not display any data and no errors too, but it's working fine if I assign a specific value to the where syntax.
Model:
public function getData() {
$where = $this->input->post('selected_holcode');
$query = $this->db->get_where("hrms.holiday", "holcode = '$where'")->result();
return $query;
Controller:
public function getHolidaylist() {
$data['record'] = $this->holiday_settings_model->getData();
$this->load->view('maintainance/holiday_settings/holiday_list', $data);
}
ajax (to display the record upon changing the dropdown menu)
<script type="text/javascript">
var controller = 'holiday_settings';
var base_url = '<?php echo site_url(); ?>';
function load_data_ajax(type){
$.ajax({
'url' : base_url + '/' + controller + '/getHolidaylist',
'type' : 'POST',
'data' : {'type' : type},
'success' : function(data){
var container = $('#holiday');
if(data){
container.html(data);
}
}
});
}
</script>
View:
<?php echo form_open('holiday_settings/getHolidaylist') ?>
<div id="holiday"></div>
<?php echo validation_errors(); ?>
<label><strong>Year</strong></label>     <label><strong>:</strong></label>
<select id="syear" onchange="load_data_ajax(1)">
<?php
for ($x=2015; $x>=2008; $x--) {?>
<option><?php echo $x;?></option>
<?php } ?>
</select></br></br>
<select name="selected_holcode" onchange="load_data_ajax(1)">
<option value="SPL">SPL</option>
<option value="LGL">LGL</option>
<option value="CMP">CMP</option>
</select></br></br>
enter code here

Answer 1

If you say that static value makes it work then your controller and model functions are working correctly I guess, Maybe you should try this:
onchange="load_data_ajax(1)" //instead of writing this
You should just pass the value like this:
onchange="load_data_ajax(this.value)"
Or as I see you are using JQuery, you can also do this:
<select name="selected_holcode" class="toggler" > <!-- Remove the onchange event and add a new class to the element -->
<script type="text/javascript">
$(function(){ //on page load
$(".toggler").on("change", function(){
var value_to_send = $(this).val(); //get the selectbox value here
//your ajax call goes here
});
});
</script>

Answer 2

im not sure but try this:
<select name="selected_holcode" onchange="load_data_ajax(this.value)">
instead of : load_data_ajax(1)
or
onchange="load_data_ajax(this.options[this.selectedIndex].value)
if your Dropdown was filled with dynamic data from DB
// EDIT
And what do you want to do if syear is changed?
since you call the same function? and you should set it like this:
for ($x=2015; $x>=2008; $x--) {
echo "<option value='$x'>$x</option>";
}
Now you can get your value to your onchange function like i already said