Answers for "datatables size columns"

datatables change width of columns

$('#example').dataTable( {
  "autoWidth": false, // might need this
  "columns": [
    { "width": "20%" },
    null, // automatically calculates
    null  // remaining width
  ]
} );

datatable column width

columnDefs: [
            { width: 200, targets: 0 }
        ],

datatable width column

table.display {
  margin: 0 auto;
  width: 100%;
  clear: both;
  border-collapse: collapse;
  table-layout: fixed;         // add this 
  word-wrap:break-word;        // add this 
}