Show the lifecycle: "I define an entity with ORM attributes, persist it with the entity manager, and call flush to write to the database. For retrieval, I use repository methods — findOneBy for single results, custom QueryBuilder methods for complex queries."
Entities are plain PHP classes that Doctrine maps to database tables. Properties map to columns using ORM attributes (#[ORM\Column], #[ORM\Id], etc.). The EntityManager handles persistence: persist() marks new entities for insertion, flush() writes all pending changes to the database. Repositories provide methods for querying: findOneBy(), findBy(), and custom query methods using QueryBuilder or DQL. Symfony generates repositories automatically when you specify repositoryClass in the entity attribute. Strong candidates explain: that entities should not depend on the framework, the difference between persist and flush, that flush is a single database transaction, and the make:entity command for scaffolding.
Entry-level Doctrine question. Candidates who cannot explain the persist/flush distinction will misuse the entity manager. Those who understand that flush batches all changes into one transaction demonstrate basic ORM awareness.