clear datatable initialize once data is fetch

if you're using DataTables 1.10.x, you can initialize the new table with
additional option "destroy": true, see below : 

function fetchNews(context)
{
     if(context!="")
     {
        $("#dailyNews").dataTable({
            "destroy": true,
            // ... skipped ...
        });
    }
}

OR

For older versions :

function fetchNews(context)
{
     if(context!="")
     {
        // Destroy the table
        // Use $("#dailyNews").DataTable().destroy() for DataTables 1.10.x
        $("#dailyNews").dataTable().fnDestroy()

        $("#dailyNews").dataTable({
           // ... skipped ...
        });
    }
}