I am using
gem 'jquery-datatables-rails', '3.4.0'
gem 'ajax-datatables-rails'
My CoffeeScript for this table looks like
# Datatables
$ ->
table = $('#qr-submissions-table').dataTable
dom: 'C<"clear">lfrtip'
processing: true
serverSide: true
ajax: $('#qr-submissions-table').data('source')
pagingType: 'full_numbers'
columns: [
{data: 'custom_columns'}
{data: 'delivery_number' }
{data: 'qpi_department' }
{data: 'qr_client' }
{data: 'date_submitted'}
{data: 'bay_number' }
{data: 'submitted_by'}
{data: 'delivery_note'}
{data: 'ops' }
]
"order": [[ 3, "desc" ]]
columnDefs: [
{ "orderable": false, "targets": [3, 7, 8]},
{"targets": 1, visible: ($("#delivery_number_show").val() == 'true')},
{"targets": 2, visible: ($("#division_show").val() == 'true')},
{"targets": 3, visible: ($("#client_show").val() == 'true')},
{"targets": 4, visible: ($("#scan_time_show").val() == 'true')},
{"targets": 5, visible: ($("#delivery_location_show").val() == 'true')}
{"targets": 6, visible: ($("#submitted_by_show").val() == 'true')},
{"targets": 7, visible: ($("#delivery_note_show").val() == 'true')},
{"targets": 8, visible: ($("#photo_show").val() == 'true')},
]
Here the custom column field is hash like '{ "name1" : "value1", "name2" : "value2" }' .. How can i display this as coulm names and values. name1 and name2 will be column headers and value1 and value2 will be corresponding row values.each row has different values for 'value1' and 'value2'. Is there any way to do this? Please help?

Unfortunately I don't know Ruby-on-rails, but I DO know jQuery DataTables.
If your JSON response looks like this:
AND the name of your columns will be fixed (in your example: "name1" and "name2"), you can do something like this (I'll provide you 2 ways of achieving it in the same example):
Note: In this case I'm trying to emulate your custom column field with the key Name
But, if your columns will be dynamic (names could change), you'll need to do something like this: Example