求大神帮忙看看~

<?php
                    $link = mysqli_connect("localhost","root","");
                    mysqli_select_db($link,"messageboard");
                    $query = "select * from message";
                    $result = mysqli_query($link,$query);
                    if( mysqli_num_rows($result) < 1){
                        echo " 目前数据表中还没有任何留言!";
                    }else{
                        $totalnum = mysqli_num_rows($result);//获取数据库中所有数据条数
                        $pagesize = 7;//每页显示7条
                        if(empty($page) || !is_numeric($page) || $page < 1){$page = 1;}
                        if( $page == ""){
                            $page = 1;
                        }
                        $begin = ($page-1)*$pagesize;
                        $totalpage = ceil($totalnum/$pagesize);
                        echo "<table border=0 width=95%><tr><td>";
                        $datanum = mysqli_num_rows($result);
                        echo "共有".$totalnum."条留言，每页".$pagesize."条，共".$totalpage."页。<br>";
                        for( $i = 1; $i <= $totalpage; $i++){
                            echo "<a href=ceshi1.php?page=".$i.">[".$i."] </a>";
                        }
                        echo "<br>";
    43                 $query = "select * from message order by addtime desc limit $begin,$pagesize";
    44                 $result = mysqli_query($link,$query);
    45                    $datanum = mysqli_num_rows($result);
                        for( $i = 1; $i <= $datanum; $i++){//$datanum???
                            $info = mysqli_fetch_array($result);
                 echo "<li><h4>".$row['author']."</h4>
                 <small>".$row['addtime']."</small>
                 <p>".$row['content']."</p></li>";}
                        }
                    mysqli_close($link)
                 ?>wamp报错：Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given in C:\wamp64\www\message\ceshi1.php on line 45 $datanum = mysqli_num_rows($result);也就是这一行错误，跪求~