Try the below code to adjust the column width in data table
For the first column
$('#example').dataTable( {
"columnDefs": [
{ "width": "20%", "targets": 0 }
]
} );
For more details check columns.width
For a specific column.
$('#table_1').DataTable({
columns: [
{ data: 'id', name: 'id' , width: '50px', class: 'text-right' }
]
});