Configuration

First of all you will need to configure the database connection. We will assumme you have followed the previous tutorials and have an Oracle XE database.

parameters:
    database_driver: oci8 
    database_host: your_VM_IP
    database_port: '1521'
    database_name: XE
    database_user: your_username
    database_password: your_password
    database_charset: AL32UTF8

Database charset is by default AL32UTF8 in Oracle XE but if you have to move your database to another Oracle version I would recommend to specify it explicitely in the configuration.
You need to make sure you have the following parameter in your app/config/config.yml

doctrine:
    dbal:
        charset:  %database_charset%

Adding a listener

You need then to add a custom listener to handle the session properly.

services:
    oracle.listener:
        class: Doctrine\DBAL\Event\Listeners\OracleSessionInit
        tags:
            - { name: doctrine.event_listener, event: postConnect }

SonataPageBundle and Oracle

Doctrine does not support where conditions on CLOB. You need to update your schema using the following PR https://github.com/sonata-project/SonataPageBundle/pull/104

Doctrine and Oracle

Finally there are a few known issues between Oracle and Doctrine

http://docs.doctrine-project.org/projects/doctrine-dbal/en/latest/reference/known-vendor-issues.html#oracle