The Power ORM


RedBeanPHP supports self-referential relationships. In RedBeanPHP terminology, these are called trees. Here is an example, let's decorate a christmas tree with some candy canes:

    $cane R::dispense('cane',10);
$cane[1]->ownCane = [ $cane[2], $cane[9] ];
$cane[2]->ownCane = [ $cane[3], $cane[4] ];
$cane[4]->ownCane = [( $cane[5],
$cane[7], $cane[8] ];
$cane[5]->ownCane = [ $cane[6] ];
$id R::store$cane[1] );
$root R::load'cane'$id );

//outputs: 6

Trees are just a special case of lists, you use a list with the same name as the parent type. In the example script above, a cane has an ownCaneList. Another example: page->ownPageList. As you can see in the example above you can navigate the lists using the IDs.


Instead of manually looping through each own-list of a bean you can use the traverse() method:

    $page->traverse'ownPage', function( $page ) {
    } );

This allows you to recursively apply a function to a list. To limit the results when accessing a list you can use the with/withCondition() method:

    $page->with' LIMIT 10 ')->traverse( ... );
$page->withCondition'  rating > ? ', [ ] )->traverse( ... );

You can also use withCondition and alias together with the traverse function.

Use the third parameter to specify the maximum depth:

    $page->traverse'ownPage'$func); //max 3 levels

Use the PHP use statement to import variables into the function scope:

    $task->traverse'ownTask', function( $task ) use ( &$todos ) {
$todos[] = $task->name;
    } );

The traverse() function does not check for recursion in trees.

Traversing upwards

You can also traverse the other way around, here is a quick example:

    $page R::dispense('page');
$page->title 'chapter';
$page2 R::dispense('page');
$page2->title 'article';
$page3 R::dispense('page');
$page3->title 'text';
$page->ownPageList[] = $page2;
$page2->ownPageList[] = $page3;
$p $page3->fresh();
$p->traverse('page', function($parent) {

Importing Trees

Do you want to import a hierarchical data structure ? This can be accomplished using the R::dispense() feature.

Faster trees (5.2+)

If your database supports common table expressions (Postgres, MariaDB 10.3+) you can use the CTE-based tree tools as well:

    $pages R::dispense(array(
'_type' => 'page',
'title' => 'home',
'ownPageList' => array(array(
'_type' => 'page',
'title' => 'shop',
'ownPageList' => array(array(
'_type' => 'page',
'title' => 'wines',
'ownPageList' => array(array(
'_type' => 'page',
'title' => 'whiskies',

Given the page hierarchy of the shop above you can use R::parents() and R::children() like this:

    R::parents$whiskyPage' ORDER BY title ASC ' );
//gives: home,shop,whiskies,wines
R::children$homePage' ORDER BY title ASC ' ) );
R::children$winePage' title NOT IN (\'wines\') ORDER BY title ASC ' );
R::parents$winePage'  title NOT IN (\'home\') ORDER BY title ASC ' );

Because this approach uses common table expressions the performance is much better.

Caution! This is a new, experimental feature available as of RedBeanPHP 5.2. The CTE API has been tested but may still contain bugs. Also the CTE API may be subject to change in future versions.

Counting in Trees (5.5)

To count beans in trees use R::countParents() or R::countChildren.

    R::countParents$whiskyPage );
R::countChildren$winePage' title != :title  ', [ ':title' => 'wines' ] );

As of 5.6 you can add your own SELECT clause like 'count(distinct vendor)'. By default, countChildren() and countParents() subtract 1 from total number of counted records to exclude the starting bean. If you provide your own select clause (or an SQL snippet), this might not make sense, so it won't happen in that case.

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