Add calculated column from server side script in datatables - php

Question

I am using jQuery datatable in my php code.
my server server-side processing script here
$columns = array(
array( 'db' => 'val1', 'dt' => 0 ),
array( 'db' => 'val2', 'dt' => 1 ),
);
here problem is that how i get another unbound column val3
which have value of val1+val2 .
Example :
val1 val2 val3
1 2 3
3 5 8
here val1 and val2 is database column and val3 is calculated column.
I am stuck right now that how to add val3 column from server-side script.
Any help is appreciated.

Answer 1

You need to write DB query from server side for getting 3rd column.
Client side keep 3 columns table code (html)
<table class="table results" border="1">
<thead>
<tr>
<th>val1</th>
<th>val2</th>
<th>val3</th>
</tr>
</thead>
</table>
Client side define 3 columns (jquery datatable)
results= $(".results").dataTable({
aLengthMenu: [ [10, 25, 50, 100, 150, "-1"], [10, 25, 50, 100, 150, "All"] ],
iDisplayLength: 10,
searching: true,
"aaSorting": [],
"order": [[ 0, "desc" ]],
"sPaginationType": "full_numbers",
"bProcessing": true,
"serverSide": true,
"bDestroy": true,
"cache": false,
"sAjaxSource": "<?php echo $serverside_php; ?>",
"sDom": 'T<>lfrtip',
"oTableTools": {
"sRowSelect": "os",
"aButtons": [ "select_all", "select_none" ]
},
"aoColumnDefs": [
{ "bSortable": false },
{ "data": "val1" },
{ "data": "val2" },
{ "data": "val3" },
],
});
Feed the server side response data to client datatable + html