What does `$this->_identifier` contain in your failing case?
It contains for example
array( [id] => );
Because on db you find an empty string and not a null value.
If I get it correctly, you are using empty strings to emulate NULL references, which is invalid in SQL ( I've explained it extensively at http://stackoverflow.com/questions/15502408/doctrine-2-use-default-0-values-instead-of-null-for-relation/15511715#15511715 )
Is this what you are doing? Because for any identifier that is not NULL an attempt to load it should be run, regardless of its content.
That's not me 
It's the system by which i'm sharing the db.
It uses MyIsam engine with no fk or index, so i've found this way to skip load when on db i've empty strings.
Are there other (maybe cleaner) ways?
Thanks,
Gabriele
No, the only correct way to handle this is to set NULL values for the association meta-columns. Marking as invalid
I can't find doc about it: https://doctrine-orm.readthedocs.org/en/latest/reference/annotations-reference.html?highlight=column#annref-column
Can you give an example?
`$this->someAssociation = NULL;`. That's basically what I mean.
Mmm, didn't understand.
Anyway, we've tried to fix the old Delphi Monster witch store empty strings instead of nulls... with no results.
So, here is my workaround, maybe this can be useful for other developers who will be in troubles in the future..
In "UnitOfWork" class, public method "createEntity".
[...]
// TODO: Is this even computed right in all cases of composite keys? foreach ($assoc['targetToSourceKeyColumns'] as $targetColumn => $srcColumn) { $joinColumnValue = isset($data[$srcColumn]) ? $data[$srcColumn] : null; // START-EDIT // GT: our moas store empty string instead of null in fk columns. // So, let's check and handle it as null! if (empty($joinColumnValue)) $joinColumnValue = null; // END-EDIT if ($joinColumnValue !== null) { if ($targetClass->containsForeignIdentifier) { $associatedId[$targetClass->getFieldForColumn($targetColumn)] = $joinColumnValue; } else { $associatedId[$targetClass->fieldNames[$targetColumn]] = $joinColumnValue; } } }
[...]
Regards,
Gabriele
Gabriele Tondi the ORM does not deal with such architectures (nor with generally invalid usage of RDBMS systems). The only acceptable solution in ORM is with correct NULL values, as it should be, so this patch is invalid.