Latest Doctrine versions are removing features that we use on Symfony Docs. We should double check everything, remove no longer relevant docs and provide alternatives when possible:

Changes already included in Doctrine 2.x

(we can already make these changes in Symfony Docs)

• Removed support for entity namespace aliases:App:User no longer works, useUser::class orApp\Entity\User:doctrine/orm@63cb801
• Removed support for same-namespace class resolution. Now you must use::class in annotations:doctrine/orm@cd590f2

  /**-    @ORM\ManyToOne(targetEntity="NotifyChangedEntity", inversedBy="items") */+    @ORM\ManyToOne(targetEntity=NotifyChangedEntity::class, inversedBy="items")*/

• Removed support for named queries:doctrine/orm@e6557cb
• RemovedEntityManager::copy:doctrine/orm@c4eb2b0
• Removed reverse engineering (convert:mapping) and entity generation (generate:entity):doctrine/orm@e4ce75a

Changes planned for the upcoming Doctrine 3.x

(please don't make any of these changes until Doctrine 3 is released)

• Removed the YAML metadata driver: you can no longer define the entity using YAML. Only XML and annotations.doctrine/orm@bc0c098
• RemovedEntityManager::detach:doctrine/orm@df397e1
• Removed PDO dependency: the support ofPDO::PARAM_*,PDO::FETCH_*,PDO::CASE_* andPDO::PARAM_INPUT_OUTPUT constants in the DBAL API is removed. \Doctrine\DBAL\Driver\PDOStatement does not extend \PDOStatement anymore:Remove hard dependency on PDO doctrine/dbal#2958