How to connect to multiple db in a php file?

Question

I am using DBAL with Doctrine to make a connection in Symfony 3 to a database. What I'd like to do is to have all my queries in a PHP file, not in a controller.

In a controller I can use this:

$conn = $this->get('doctrine.dbal.database2_connection');

to get a connection, but in a simple PHP I cannot.

So, I don't know how to call multiple connections without using the EntityManagerobject because I'm not working with an Entity class.

Answer 1

If you use PDO, every connection is treated as an object, and you can have an arbitrary number of them simultaneously. Check out the docs

Answer 2

To achieve what you want to need to master the next things:

1. You need to check how to work with multiple databases (I guess that's what you mean by many connections) in the documentation.

2. Also, you need to see how to create custom repositories.

3. You will need to use DQL (doctrine query language) to do your own queries.

4. And the last point is that you need to get used with Symfony's dependency injection.

Feel free to skip everything you already know. I can't detail everything here because your question is quite vague. So this answer will guide on how to find your solution or at least focus your question.

Answer 3

Symfony Allows you to connect multiple databases. You need to do a bt workout to achieve this.

Step#1

Add parameters to parameters.yml file. The second database connection could be added using the following parameters:

Parameters:

# First database

  database_host: 127.0.0.1   
  database_port: null   
  database_name: qmsfumgabd  
  database_user: qmsfumgabd 
  database_password: xxx9bxxMxx

# Second database

  database2_host: 127.0.0.1 
  database2_port: null 
  database2_name: huscqxzwaw
  database2_user: huscqxzwaw
  database2_password: dxxxFXxxxB

Step#2

The next step is to get these credentials in the config.yml:

doctrine:

  # Configure the abstraction layer

  dbal:

      # Set the default connection to default

      default_connection: default

      connections:

          default:

                driver: pdo_mysql

                host: '%database_host%'

                port: '%database_port%'

                dbname: '%database_name%'

                user: '%database_user%'

                password:  '%database_password%'

                charset: UTF8

         database2:

               driver:    pdo_mysql

               host:      '%database2_host%'

               port:      '%database2_port%'

               dbname:    '%database2_name%'

               user:      '%database2_user%'

               password:  '%database2_password%'

               charset:   UTF8

Step#3

Finally, specify the mapping of each bundle in the project:

# Configure the ORM

  orm:

      default_entity_manager: default

      entity_managers:

          # Register which bundle should use which connection

          default:

              connection: default

              mappings:

                  AppBundle:  ~

                  DemoBundle: ~

          database2:

              connection: database2

              mappings:

                  CloudwaysBundle: ~

Step#4

Now for calling any of the entity manager use connection names simply:

class UserController extends Controller

{

   public function indexAction()

   {

       // All 3 return the "default" entity manager

       $em = $this->getDoctrine()->getManager();

       $em = $this->getDoctrine()->getManager('default');

       $em = $this->get('doctrine.orm.default_entity_manager');



       // Both of these return the "database2" entity manager

       $anotherEm = $this->getDoctrine()->getManager('database2');

       $anotherEm = $this->get('doctrine.orm.database2_entity_manager');

   }

}

You can also take help from symfony's documentation for multiple databases.