树形结构数据存储方案(一):邻接列表模式
<?php
// $parent is the parent of the children we want to see
// $level is increased when we go deeper into the tree,
// used to display a nice indented tree
function display_children($parent, $level)
{
// 获得一个 父节点 $parent 的所有子节点
$result = mysql_query('SELECT name FROM tree WHERE parent="'.$parent.'";');
// 显示每个子节点
while ($row = mysql_fetch_array($result))
{
// 缩进显示节点名称
echo str_repeat(' ',$level).$row['name']."\n";
//再次调用这个函数显示子节点的子节点
display_children($row['name'], $level+1);
}
}
?>
来源: http://blog.jobbole.com/112309/