Question

如果有人试图打开下一页，我试图让我自己的分页系统忽略新数据：

示例：

我有这张桌子：

1. apple
2. orange 
3. banana
4. burger
5. pizza 
6. spaghetti

我每页只显示3行。

mysql查询：

// $page = 0 for first page
$sql = "SELECT * FROM mytable ORDER BY id DESC LIMIT $page, 3";

结果是这样的

第1页：

6. spaghetti
5. pizza
4. burger

第2页：

3. banana
2. orange
1. apple

让我们说现在我在第1页，其他人添加了3个新行：

water
juice
coffee

现在将会发生的事情是，如果我转到第2页，我会得到一个重复的页面！

现在第2页将会是：

6. spaghetti
5. pizza
4. burger

原因是因为第1页显示了新数据：

 9. water
 8. juice
 7. coffee

如果用户没有刷新第一页并且只想查看第二页，我怎么能阻止这种情况发生呢？

这是一个问题，特别是如果你试图使你的分页看起来就像推特！

Answer 1

// find out how many rows are in the table 
$sql = "SELECT COUNT(*) FROM mytable";
$result = mysql_query($sql, $conn) or trigger_error("SQL", E_USER_ERROR);
$r = mysql_fetch_row($result);
$numrows = $r[0];

// number of rows to show per page
$rowsperpage = 10;
// find out total pages
$totalpages = ceil($numrows / $rowsperpage);

// get the current page or set a default
if (isset($_GET['currentpage']) && is_numeric($_GET['currentpage'])) {
   // cast var as int
   $currentpage = (int) $_GET['currentpage'];
} else {
   // default page num
   $currentpage = 1;
} // end if

// if current page is greater than total pages...
if ($currentpage > $totalpages) {
   // set current page to last page
   $currentpage = $totalpages;
} // end if
// if current page is less than first page...
if ($currentpage < 1) {
   // set current page to first page
   $currentpage = 1;
} // end if

// the offset of the list, based on current page 
$offset = ($currentpage - 1) * $rowsperpage;

// get the info from the db 
$sql = "SELECT * FROM mytable ORDER BY id DESC LIMIT $offset, $rowsperpage";
$result = mysql_query($sql, $conn) or trigger_error("SQL", E_USER_ERROR);

// while there are rows to be fetched...
while ($list = mysql_fetch_assoc($result)) {
   // echo data
   echo $list['id'] . " : " . $list['number'] . "<br />";
} // end while

/******  build the pagination links ******/
// range of num links to show
$range = 3;

// if not on page 1, don't show back links
if ($currentpage > 1) {
   // show << link to go back to page 1
   echo " <a href='{$_SERVER['PHP_SELF']}?currentpage=1'><<</a> ";
   // get previous page num
   $prevpage = $currentpage - 1;
   // show < link to go back to 1 page
   echo " <a href='{$_SERVER['PHP_SELF']}?currentpage=$prevpage'><</a> ";
} // end if 

// loop to show links to range of pages around current page
for ($x = ($currentpage - $range); $x < (($currentpage + $range) + 1); $x++) {
   // if it's a valid page number...
   if (($x > 0) && ($x <= $totalpages)) {
      // if we're on current page...
      if ($x == $currentpage) {
         // 'highlight' it but don't make a link
         echo " [<b>$x</b>] ";
      // if not current page...
      } else {
         // make it a link
         echo " <a href='{$_SERVER['PHP_SELF']}?currentpage=$x'>$x</a> ";
      } // end else
   } // end if 
} // end for

// if not on last page, show forward and last page links        
if ($currentpage != $totalpages) {
   // get next page
   $nextpage = $currentpage + 1;
    // echo forward link for next page 
   echo " <a href='{$_SERVER['PHP_SELF']}?currentpage=$nextpage'>></a> ";
   // echo forward link for lastpage
   echo " <a href='{$_SERVER['PHP_SELF']}?currentpage=$totalpages'>>></a> ";
} // end if
/****** end build pagination links ******/
?>

Answer 2

您可以使用此类内容来为您的表格项目进行正确的分页。你可以删除ORDER BY＆amp; DESC知道sql查询结果如何变化。

$page; // $page is current page
$result = 3; // As you need 3 results per page.
$offset = ($page * $result) - $result;

$sql = "SELECT * FROM mytable ORDER BY id DESC LIMIT $result OFFSET $offset";

Answer 3

我不得不使用session来让它按照我想要的方式工作，而这就是我如何解决它：

$count = $PDO->query("SELECT id FROM mytable")->rowCount(); //count rows
if(!isset($_SESSION['rowCount']))
{
 $_SESSION['rowCount'] = $count; // save row counts 
}

if(isset($_GET['page']))
{
   $offset = ($_GET['page'] -1) * 3 + $count - $_SESSION['rowCount'];
}
else
  $offset = 0;
  $sql = $PDO->prepare("SELECT * FROM mytable ORDER BY id DESC LIMIT $offset, 3");
  $sql->execute();

当用户回到第1页时，我也取消了会话。

php分页：如果添加了新数据，第2页显示相同的第1行

3 个答案: