sColumns in json output from server to show added columns

sColumns is used by DataTables only for reordering columns (by name) not my column number you are setting in javascript, it will help reordering added columns by this class if we want to show only added columns on html table.

check this forum post
https://www.datatables.net/forums/discussion/950/scolumns-not-defined-and-data-doesn-load