2

I am using Paris (which is built on top of Idiorm).

I have the following Model classes (example inspired from the documentation on github):

<?php
class Post extends Model {
    public function user() {
        return $this->belongs_to('User');
    }
}

class User extends Model {
    public function posts() {
        return $this->has_many('Post'); // Note we use the model name literally - not a pluralised version
    }
}

So now I can do the following (works well):

// Select a particular user from the database
$user = Model::factory('User')->find_one($user_id);
// Find the posts associated with the user
$posts = $user->posts()->find_many();

// Select a particular post from the database
$post = Model::factory('Post')->find_one($post_id);
// Find the user associated with the post
$user = $post->user()->find_one();

But I'd like to do the following aswell:

$posts = Model::factory('Post')->find_many();
foreach ($posts as $post) {
     echo($post->user()->find_one()->username); // generates a query each iteration
}

Unfortunately this creates a query for each iteration. Is there a way to tell Paris or Idiorm to take the associated information in the first find_many query ?

How are you supposed to retrieve information with Paris to minimize the numbers of query ? I'd like not to have to manually specify the join condition (this is the reason why I am using Paris and not Idiorm)

Benjamin Crouzier
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2 Answers2

4

I am the current maintainer of the Paris and Idiorm projects. Unfortunately what you describe here is a case for a custom query and not something that Paris was ever built to solve. The philosophy of Paris and Idiorm is to stick as close to the 80/20 principle as possible and your use case is in the 20.

It would be interesting to know how you ended up solving this problem.

Treffynnon
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    So far, I only worked around the problem. On one project, I just switch to Rails. On the other project, I use a mixture of Idiorm and Paris, and all complex requests are done with joins in Idiorm. I really don't like mixing both Idiorm and paris, so I might come back and actually solve the problem. +1 for maintaining the project. – Benjamin Crouzier Jan 15 '13 at 16:27
0

I've had exactly the same problem, and ended up with this (a bit ugly) solution:

$posts = Model::factory('Post')...->limit($perpage)->find_many();
$user_ids = $user_lookup = array();

foreach($posts as $post) $user_ids[] = $post->user_id;

$users = Model::factory('User')->where_id_in($user_ids)->find_many();
foreach($users as $user) $user_lookup[$user->id] = $user;

Only 2 selects. And later in template:

{% for post in posts %}
   <h2>{{ post.title }}</h2>
   by author: {{ user_lookup[post.user_id].username }}
{% endfor %}

But it only works if you don't have hundreds of posts showing on one page.

bibinka
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