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How to check if an entity exists in a Database without loading it?

#1
EKKEKK
Joined on 2013-03-05

Hi,

I am trying to speed up some code - where i check if an entity exists in order to make a decision.

In Java - It looks like this (pk - is the primary key of the entity): 

MyClass find  = em.find(MyClass.class, pk);

boolean exists = find != null;

Is there a way to check the existence without loading the entity?

Thanks

 

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#2
supportsupport
Joined on 2010-05-03

You can use a query: 

SELECT e.pk FROM MyClass e WHERE e.pk = :pk

or 

SELECT COUNT(e) FROM MyClass e WHERE e.pk = :pk

 

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