douli8428 2010-01-20 00:00
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如何知道数据库中是否存在关系中的对象

I'm using Symfony with Doctrine.

I have two classes defined, Person and Student, a relation one to one.

Each Student is related to a Person, but not every Person has a relation with a Student.

When I call ...

$person->getStudent();

... I always get and object, regardless some Person's doesn't have a Student. How can I know it doesn't (the Student) exist in the database?

Thanks.

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  • drmcm84800 2010-01-20 00:45
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    I think

    $person->getStudent()->exists();
    

    should do it. At least according to the Doctrine API documentation.
    The object you get is probably some kind of Null record.

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