小编hen*_*hen的帖子

.tableUpdates {
        overflow-y: auto;
        height: 250px;
    }

    .tableUpdates thead th {
        position: sticky;
        margin-top:0px;
        top: 0;
        background: #DC3545;
    }

<div class="col-md-4 pr-0 tableUpdates">
    <table class="table table-bordered table-hover">

           <thead class="bg-danger text-light">
               <tr>
                  <th>Header</th>
               </tr>
            </thead>
            
            <tbody>
               .....some rows
            </tbody>
    </table>
</div>