<input type="text" class="form-control" id="tableName" placeholder="请输入表格名称" data-toggle="tooltip" data-placement="top">
<script>
function showPopover(target, msg) {
  target.attr("data-original-title", msg);
  $('[data-toggle="tooltip"]').tooltip();
  target.tooltip('show');
  target.focus();
  //2秒后消失提示框
  var id = setTimeout(
    function () {
      target.attr("data-original-title", "");
      target.tooltip('hide');
    }, 2000
  );
}
showPopover($("#tableName"),"表名已存在");
</script>