I have a situation where Doctrine generates a wrong SQL query and crashes with an exception.
The userland code calls the EntityManager::merge method.
The query generated looks like "SELECT FROM SomeTable", meaning it has no select column list, and therefore it's plainly wrong.
The entity I am trying to merge back into the entity manager is a regular entity with state detached. The class has a column which is declared as ID and filled with an autogenerated value, three regular columns, and a one-to-many relationship. The to-many-relationship causes BasicEntityPersister::loadOneToManyCollection() to be called, which in turn calls BasicEntityPersister::_getSelectEntitiesSQL, which then calls BasicEntityPersister::_getSelectColumnListSQL, which wrongly returns an empty string, thus leading to the corrupt query without a select column list being generated. The target entity of the one-to-many relationship is a mapped superclass, which has an ID (again with autogenerated values), and a many-to-one relationship inversing the one in the first entity. Further fields depend on its exact type as determined by the inheriting entities, but it will always have some.
Here is the exception, up to the point where the trace leaves the ORM:
exception 'PDOException' with message 'SQLSTATE: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FROM VersionedDataObject t0' at line 1' in /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/DBAL/Connection.php:577 Stack trace: #0 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/DBAL/Connection.php(577): PDO->query('SELECT FROM Ve...') #1 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/ORM/Persisters/BasicEntityPersister.php(1173): Doctrine\DBAL\Connection->executeQuery('SELECT FROM Ve...', Array) #2 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/ORM/UnitOfWork.php(1984): Doctrine\ORM\Persisters\BasicEntityPersister->loadOneToManyCollection(Array, Object(persistentData\model\versioning\InputComponentDataVersion), Object(Doctrine\ORM\PersistentCollection)) #3 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/ORM/PersistentCollection.php(207): Doctrine\ORM\UnitOfWork->loadCollection(Object(Doctrine\ORM\PersistentCollection)) #4 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/ORM/UnitOfWork.php(1441): Doctrine\ORM\PersistentCollection->initialize() #5 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/ORM/UnitOfWork.php(1323): Doctrine\ORM\UnitOfWork->doMerge(Object(persistentData\model\versioning\InputComponentDataVersion), Array) #6 /var/www/invoiceCreator/src/thirdPartyComponents/doctrine/Doctrine/ORM/EntityManager.php(520): Doctrine\ORM\UnitOfWork->merge(Object(persistentData\model\versioning\InputComponentDataVersion))
This one is a blocker by user standards. The error means that it is impossible to use Doctrine in long-running batch jobs like in my situation, because it does not support merging certain detached objects back into the entity manager at all, while at some point they need to be detached for virtual memory capacity reasons.