2011-08-17-pdo-fetch-group.markdown

layout	title
post	Fetching groups with PDO

PDO offers a very usefull option in it's fetchMode : PDO::FETCH_GROUP which allows you to group entries by category.

Table Example:

{% highlight html %} test_user : +----+-----------+----------+-------+ | id | firstname | lastname | city | +----+-----------+----------+-------+ | 1 | Jean | Machin | Paris | | 2 | Jean | Truc | Nice | | 3 | Paul | Bla | Nice | +----+-----------+----------+-------+ {% endhighlight %}

{% highlight php %}

query("SELECT u.city, u.id, u.firstname, u.lastname FROM test_user u") ->fetchAll(PDO::FETCH_ASSOC | PDO::FETCH_GROUP); ?>

{% endhighlight %}

Result (in YAML) :

{% highlight yaml %} Paris: - { id: 1, firstname: Jean, lastname: Machin } Nice: - { id: 2, firstname: Jean, lastname: Truc } - { id: 3, firstname: Paul, lastname: Bla } {% endhighlight %}

With another query :

{% highlight mysql %} SELECT u.firstname, u.id, u.lastname, u.city FROM test_user u {% endhighlight %}

{% highlight yaml %} Jean: - { id: 1, lastname: Machin, city: Paris } - { id: 2, lastname: Truc, city: Nice } Paul:
- { id: 3, lastname: Bla, city: Nice } {% endhighlight %}