如何从mysql获取分层菜单

发布于 2024-09-06 21:36:56 字数 544 浏览 2 评论 0原文

我有一个带有分层菜单的表格，例如

"id" "parent_id" "name"
1 0 menu
2 1 item1
3 2 item1_1
4 1 item2
5 4 item2_1
...
...

，这里有数百个菜单项。为了获取数组中的所有项目，我必须编写一个像这样的递归函数，

getmenu function(parent_id = 1)
{
  $items = mysql_query("SELECT id FROM table WHERE parent_id = " + parent_id);
  while ($item = msyql_Fetch_assoc($items)) {
    ...here I put them in array and call recursive function again to get sub items...
    getmenu($item['id']);
  }   
}

但这会执行数百个查询。这是从数据库获取分层菜单的最佳方法吗？这种方式对mysql的负载大吗？

原文

I have a table having hierarchical menus like

"id" "parent_id" "name"
1 0 menu
2 1 item1
3 2 item1_1
4 1 item2
5 4 item2_1
...
...

and I have 100s of menu items here. In order to get all items in an array I have to write a recursive function like this

getmenu function(parent_id = 1)
{
  $items = mysql_query("SELECT id FROM table WHERE parent_id = " + parent_id);
  while ($item = msyql_Fetch_assoc($items)) {
    ...here I put them in array and call recursive function again to get sub items...
    getmenu($item['id']);
  }   
}

but this executes 100s of queries. Is this the best way to do this, to get hierarchical menus from database? Does this way loads mysql much?

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

别理我 2024-09-13 21:36:56

$stmt = "SELECT id, parent_id FROM table";
$items = Array();
$result = mysql_query($stmt);

while ($line = mysql_fetch_assoc($result)) {
    $items[] = $line;
}

$hierarchy = Array();

foreach($items as $item) {
    $parentID = empty($item['parent_id']) ? 0 : $item['parent_id'];

    if(!isset($hierarchy[$parentID])) {
        $hierarchy[$parentID] = Array();
    }

    $hierarchy[$parentID][] = $item;
}

根级别将为$hierarchy[0]。键是项目 ID，值都是直接子项。

$stmt = "SELECT id, parent_id FROM table";
$items = Array();
$result = mysql_query($stmt);

while ($line = mysql_fetch_assoc($result)) {
    $items[] = $line;
}

$hierarchy = Array();

foreach($items as $item) {
    $parentID = empty($item['parent_id']) ? 0 : $item['parent_id'];

    if(!isset($hierarchy[$parentID])) {
        $hierarchy[$parentID] = Array();
    }

    $hierarchy[$parentID][] = $item;
}

The root level will be $hierarchy[0]. Keys are items ids and values are all direct children.

回复收藏 0 原文