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Re: [eclipselink-users] If JPA Cache is enabled it's possible to get more Entitys as stored in the underlying database
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JPA will do some work to figure out which objects it needs to insert. One of
the things it will do is optimize the inserts by not running two insert
statements on the same object. It will do a number of checks to tell if two
objects are the same. It will check for objects with the same identity (i.e.
two objects that are "==") It will also check for two objects with the same @Id.
In your case when you insert the same object twice, the identity check is
bypassing the extra insert.
On 15/03/2013 10:03 AM, helmut.at.work wrote:
Thanks the "REFRESH" point me in the right direction.
There is one thing left I don't understand. My Example isn't a real world
example, but I try to understand the JPA mechanism.
In my example there are 3 ChildNodes in the Collection. 2 of them point to
the same object.
The ChildNode entity use:
...
@Id
@GeneratedValue
private long id;
...
and the ChildNode.equals uses "id" to compare objects.
Shouldn't JPA insert than 3 instead of 2 ChildNodes into DB? Seems to me
more logical.
--
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