Introduction

Introduction -- Introduction to DB_NestedSet

Overview

With this package, one can easily create trees with infinite depth inside a relational database. The package provides a way to

create/update/delete nodes
query nodes, trees and subtrees
copy (clone) nodes, trees and subtrees
move nodes, trees and subtrees
etc.

An example

Creates some root and subnodes

In this example, one rootnode and two subnodes are created, saved to the database and displayed.


<?php
require_once 'DB/NestedSet.php';
require_once 'DB/NestedSet/Output.php';
require_once 'HTML/Menu.php';
$DatabasePointer = mysql_connect("localhost", "user", "pwd");
mysql_select_db("database", $DatabasePointer);
$dsn = 'mysql://user:pwd@localhost/database';
// needed colums in table:
$params = array(
    'id'        => 'id',
    'parent_id' => 'rootid',
    'left_id'   => 'l',
    'right_id'  => 'r',
    'order_num' => 'norder',
    'level'     => 'level',
    'name'      => 'name',
);
$nestedSet =& DB_NestedSet::factory('DB', $dsn, $params);
$nestedSet->setAttr(array(
        'node_table' => 'nested_set',
        'lock_table' => 'nested_set_locks',
        'secondarySort' => 'name',
    )
);
$parent = $nestedSet->createRootNode(array('name' =>'root 1'), false, true);
$nestedSet->createSubNode($parent, array('name' => 'node 1.1'));
$nestedSet->createSubNode($parent, array('name' =>'node 1.2'));
$data = $nestedSet->getAllNodes(true);

foreach ($data as $id => $node) {
     $data[$id]['url'] = 'index.php?nodeID=' . $node['id'];
}

$params = array(
    'structure' => $data,
    'titleField' => 'name',
    'urlField' => 'url');
$output =& DB_NestedSet_Output::factory($params, 'Menu');
$structure = $output->returnStructure();
$menu = & new HTML_Menu($structure, 'sitemap');
$menu->forceCurrentUrl($currentUrl);
$menu->show();
?>


DB_NestedSet	DB_NestedSet::addListener

DB_NestedSet

PEAR Manual