How to Use Doctrine DBAL

Edit this page

Note

This article is about the Doctrine DBAL. Typically, you'll work with the higher level Doctrine ORM layer, which uses the DBAL behind the scenes to actually communicate with the database. To read more about the Doctrine ORM, see "Databases and the Doctrine ORM".

The Doctrine Database Abstraction Layer (DBAL) is an abstraction layer that sits on top of PDO and offers an intuitive and flexible API for communicating with the most popular relational databases. The DBAL library allows you to write queries independently of your ORM models, e.g. for building reports or direct data manipulations.

Tip

Read the official Doctrine DBAL Documentation to learn all the details and capabilities of Doctrine's DBAL library.

First, install the Doctrine orm Symfony pack:

1
$ composer require symfony/orm-pack

Then configure the DATABASE_URL environment variable in .env:

1
2
3
4
# .env (or override DATABASE_URL in .env.local to avoid committing your changes)

# customize this line!
DATABASE_URL="mysql://db_user:db_password@127.0.0.1:3306/db_name?serverVersion=8.0.37"

Further things can be configured in config/packages/doctrine.yaml - see Doctrine DBAL configuration reference. Remove the orm key in that file if you don't want to use the Doctrine ORM.

You can then access the Doctrine DBAL connection by autowiring the Connection object:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
// src/Controller/UserController.php
namespace App\Controller;

use Doctrine\DBAL\Connection;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Response;

class UserController extends AbstractController
{
    public function index(Connection $connection): Response
    {
        $users = $connection->fetchAllAssociative('SELECT * FROM users');

        // ...
    }
}

This will pass you the database_connection service.

Registering custom Mapping Types

You can register custom mapping types through Symfony's configuration. They will be added to all configured connections. For more information on custom mapping types, read Doctrine's Custom Mapping Types section of their documentation.

1
2
3
4
5
6
# config/packages/doctrine.yaml
doctrine:
    dbal:
        types:
            custom_first:  App\Type\CustomFirst
            custom_second: App\Type\CustomSecond

Registering custom Mapping Types in the SchemaTool

The SchemaTool is used to inspect the database to compare the schema. To achieve this task, it needs to know which mapping type needs to be used for each database type. Registering new ones can be done through the configuration.

Now, map the ENUM type (not supported by Doctrine DBAL by default) to the text mapping type:

1
2
3
4
5
# config/packages/doctrine.yaml
doctrine:
    dbal:
        mapping_types:
            enum: text

Note

On Doctrine DBAL 3 you can also map enum to string, but that no longer works on DBAL 4, where string columns require an explicit length. Mapping to text works on both versions.

Tip

Doctrine DBAL 4.2 added native support for the ENUM type of MySQL and MariaDB. When using DBAL 4.2 or newer, ENUM columns are introspected natively, so you don't need to register any custom mapping type for them.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.
TOC
    Version