Script21b.js

// JavaScript source code
dataTableEvents = $('#events')
    .DataTable({
        initComplete: function() {
            this.api()
                .columns()
                .every(function() {
                    var column = this;
                    var select = $("<select><option value=''></option></select>")
                        .appendTo($(column.footer()).empty())
                        .on('change',
                            function() {
                                var val = $.fn.dataTable.util.escapeRegex(
                                    $(this).val()
                                );
                                column
                                    .search(val ? '^' + val + '$' : '', true, false)
                                    .draw();
                            });

                    column.data()
                        .unique()
                        .sort()
                        .each(function(d, j) {
                            select.append("<option value='" + d + "'>" + d + "</option>")
                        });
                });

        },

    });