php分页

<?php 
// 分页
include("confge.php");

$pagesize = 5;
$url = $_SERVER['REQUEST_URI'];

echo $url."<br />";
// 查询数据库下面有多少条信息
$_numq = mysqli_query($conn, "select * from message");
$num = mysqli_num_rows($_numq);
echo $num."条信息<br />";
// 分页的公式

if($_GET["page"]){
    $pageval = $_GET["page"];
    $page = ($pageval - 1) * $pagesize;

}   
if($num > $pagesize){
    // echo $pageval."123213";
    if($pageval <= 1){
        $sageval = 1;
    }
    else{
      echo  '<a href=?='.($pageval-1).">上一页</a><<a href=?page=".($pageval+ 1).">下一页</a><br />";
    }

}

    $sql = "select * from message limit $page , $pagesize";
    echo $sql;
    $qyery =  mysqli_query( $conn,  $sql);
    while($row = mysqli_fetch_array($qyery)){
        echo  "<br/>".$row["user"]."<br />";
    }

?>