MySQL? LIMIT ? OFFSET? ???? PHP?? ?????? ??? ??? ???? ??? ??????
Jan 05, 2025 am 03:13 AMMySQL LIMIT, OFFSET with Response? ??? ??? ??
??? ??? ???? ? ??? ???? ??? ??? ??? ??? ? ?? ?? ??? ???? ??? ? ????. . MySQL? ??? ??? ???? ?? LIMIT ? OFFSET ?? ?????.
??:
????? ?? ??? ?? ?? ???? ?????? ???? ???? ????? ?? ???? ???? ???. ?????? ??? ??? ?????? ?? logic.
???:
??? ?? URL? ??? ??? ????? ?????.
http://yoursite.com/itempage.php?page=2
??? ???? ??? ??? ??? ???? ? ????. $_GET['page'].
???? ???? ???? ???? ????? SQL ??? ?????. number:
// determine page number from $_GET $page = 1; if(!empty($_GET['page'])) { $page = filter_input(INPUT_GET, 'page', FILTER_VALIDATE_INT); if(false === $page) { $page = 1; } } // set the number of items to display per page $items_per_page = 4; // build query $offset = ($page - 1) * $items_per_page; $sql = "SELECT * FROM menuitem LIMIT " . $offset . "," . $items_per_page;
? ??? ?? ????? ???? ? ?? ???? ???.
$sql = "SELECT your_primary_key_field FROM menuitem"; $result = mysqli_query($con, $sql); $row_count = mysqli_num_rows($result); // free the result set as you don't need it anymore mysqli_free_result($result); $page_count = 0; if (0 === $row_count) { // maybe show some error since there is nothing in your table } else { // determine page_count $page_count = ceil($row_count / $items_per_page); // double check that request page is in range if($page > $page_count) { // error to user, maybe set page to 1 $page = 1; } }
???? ??? ???? ??? ? ??? ??? ? ????. ??? ??? ???? ?? $page ? $page_count ??:
// later when outputting page, you can simply work with $page and $page_count to output links // for example for ($i = 1; $i <= $page_count; $i++) { if ($i === $page) { // this is current page echo 'Page ' . $i . '<br>'; } else { // show link to other page echo '<a href="/menuitem.php?page=' . $i . '">Page ' . $i . '</a><br>'; } }
? ??? MySQL? LIMIT ? OFFSET? ???? PHP?? ?????? ??? ??? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!

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