Thread

I have updated the online version of the 1.8.2 zipfiles, with fixes for the errors above, and one reported on the issue tracker (related to loading the form validation library).

Hi,
I’m here again with my many to many relationship noobs question.
What is the best way to load join field when iterating on items.
Here are the models :

class Items extends DataMapper {
    public $has_many = array(
        'lang' => array(
            'class' => 'lang',
            'other_field' => 'item',
            'join_self_as' => 'item',
            'join_other_as' => 'lang', would be 'lang_id'
            'join_table' => 'items_langs'
 ),
    );
}

class Langs extends DataMapper {
    public $has_many = array(
        'item' => array(
            'class' => 'item',
            'other_field' => 'lang',
            'join_self_as' => 'lang',
            'join_other_as' => 'item', would be 'item_id'
            'join_table' => 'items_langs'
 ),
    );
}

Now I’m loading all items and looping on them. I want to display their data and the field “name” which is a data in the joined field (ie. in the table items_langs).

I have loaded my current language and I want to display the name of the item in my language. What is the best way to do it?

$items = new Item();
$items->get();

foreach($items as $item)
{
    $item->lang->where('id', $default_language->id)->include_join_fields()->get();
    echo $item->lang->join_name;
    // Would be nice to pass related field as param like this :
    $item->include_join_fields($default_language)->get();

}

Lang is already loaded why loading it again? Any better solution?

A loop like this runs N+1 queries, which is probably not a good idea.

I would suggest getting them all in one go with something like:

$items = new Item();
$items->include_related('lang')->where_related_lang('id', $default_language->id)->include_join_fields()->get();

I don’t get why you say that lang was already loaded. I don’t see any code in your snippet that does this twice.

Update for The Example Code

Hey, i’m new to ORM, and this is the first ORM i’ve ever learned. I’ve read The DataMapper Manual and it suggested me to try the Example Project which you provided, but unfortunately the code seems not compatible with the latest CI. I’m using CI 2.1.0 and DataMapper 1.8.2.
I’m sorry for asking this, and i know you must be very busy too, but when will the example code get an update?

The example code hasn’t been looked at since CI 1.7.1. I’m afraid.

Bringing it up to date is on my todo list, which unfortunately is quite long. I can see if there is a quick fix for the current example application, but I will probably rewrite the example application for DataMapper v2.

A loop like this runs N+1 queries, which is probably not a good idea.

I would suggest getting them all in one go with something like:

$items = new Item();
$items->include_related('lang')->where_related_lang('id', $default_language->id)->include_join_fields()->get();

I don’t get why you say that lang was already loaded. I don’t see any code in your snippet that does this twice.

I load the lang based on user in parent controller (MY_Controller).
Thanks WanWizard.

@azheem,

I’ve updated the example application, and added some quick fixes to the htmlform extension to make it work.

The 1.8.2 download has been updated with these fixes, download it again if you want to try the example.

Hi i found some error after try to using example application on codeigniter 2.1.0 and datamapper 1.8.2

Fatal error: Call to undefined method CI_DB_mysql_driver::dm_call_method() in C:\wamp\www\examples\application\libraries\datamapper.php on line 1113

Then you haven’t read the docs, and didn’t install the bootstrap in your index.php file.

This is new since 1.8.2, see http://datamapper.wanwizard.eu/pages/installation.html.

Same error occur:
Fatal error: Call to undefined method CI_DB_mysql_driver::dm_call_method() in C:\wamp\www\examples\application\libraries\datamapper.php on line 1113

Any work fine version with full packaged code base include CI 2.1.0 and DataMapper1.8.2 ?
We will be greatly appreciated!

You need to add

/*
 * --------------------------------------------------------------------
 * LOAD THE DATAMAPPER BOOTSTRAP FILE
 * -------------------------------------------------------------------- *
 */
require_once APPPATH.'third_party/datamapper/bootstrap.php';

directly before the

/*
 * --------------------------------------------------------------------
 * LOAD THE BOOTSTRAP FILE
 * --------------------------------------------------------------------
 *
 * And away we go…
 *
 */
require_once BASEPATH.'core/CodeIgniter.php';

in your index.php

I thought i would just throw in the example that was in the zip when i downloaded DataMapper 1.8.2, and check out an working example to learn how to use it…. but… now I’ve tried for 3-4 hours to get it working -.-’ to find out what I’ve done wrong. Deleted everything, downloaded everything again, and copied it all ind again, many many many times. Looked through every single line in all config files, but i really can’t figure out what’s wrong -.-’

It creates the databases right, and fills some data in it, and then…
1. When I try to go forward, this shows up in the URL

hxxp://localhost/codeigniter_testing/index.php/admin/<?= site_url(‘admin/init’) ?>

annoying, but easy to jump to /admin/init.

2. On the init site where i create a user, this shows up om top of the page:

A PHP Error was encountered

Severity: Warning

Message: Invalid argument supplied for foreach()

Filename: datamapper/htmlform.php

Line Number: 52

tried filling in the form anyways.

3. Then I get a page only with this text:

Fatal error: Uncaught exception ‘Exception’ with message ‘Unable to call the method “from_array” on the class User’ in C:\wamp\www\codeigniter_testing\application\libraries\datamapper.php:1277 Stack trace: #0 [internal function]: DataMapper->__call(‘from_array’, Array) #1 C:\wamp\www\codeigniter_testing\application\controllers\admin.php(166): User->from_array(Array, Array) #2 [internal function]: Admin->init(‘save’) #3 C:\wamp\www\codeigniter_testing\system\core\CodeIgniter.php(359): call_user_func_array(Array, Array) #4 C:\wamp\www\codeigniter_testing\index.php(203): require_once(‘C:\wamp\www\cod…’) #5 {main} thrown in C:\wamp\www\codeigniter_testing\application\libraries\datamapper.php on line 1277

This is really really pissing me off xD I thought I was about to learn about the DataMapper, but ended up using 3-4 hours trying to get the example working, without luck -.-’ Really hope someone can help me xD

GREAT JOB WanWizard! I have been waiting for this update.

I follow the install tutorial and it worked out of the box with no issues, and we have a decent size system.

One question tho, I know CI 2.1 now has a PDO driver. Does ORM works with PDO? If that is the case, how? I tried just changing the driver to ‘pdo’. in the ci database.php config file.

But I get this error message

Uncaught exception ‘PDOException’ with message ‘invalid data source name’ in ...

Then you haven’t read the docs, and didn’t install the bootstrap in your index.php file.

This is new since 1.8.2, see http://datamapper.wanwizard.eu/pages/installation.html

thank’s works for me. Just some advice, maybe you should update the offline documentation. :D

Can I combine this plugin with ionAuth? I see the structure of database table seems same. any suggestion where I’m start