Actually, another option is just to overwrite B so the key stays the
same but the data in it changes.
On 20 Jan 2010, at 15:31, Alan She wrote:
Thanks! This really a smart way for relations that often changes.
But I wonder if this is the only way?
What if the relation seldom change?
I believe the cost of the indirection will be shown on
the complexity of code and the runtime performance,
if using the "resolution" Entity everywhere.
On 1月20日, 下午3時37分, John Patterson <jdpatter...@gmail.com>
wrote:
If you are going to change the relation often you might want to
have a
"resolution" Entity in the middle - lets say CurrentB.
A->CurrentB->B
instead of updating every A just update the single CurrentB
On 20 Jan 2010, at 14:05, Alan She wrote:
Assume I have two class A and B,
which is unidirection unowned many to one relationship. (A * ----> 1
B)
I store the Key of class B inside class A.
The code looks like this, (I am using JPA)
@Entity
public class A {
@Enumerated
private Key bKey;
}
@Entity
public class B {
}
Both A and B instance of the same user are under the same entity
group.
When I need to delete B, lets say 'Bx'
any A that associate with 'Bx' is going to change the association to
'By'.
I can do this by query and iterate update with low level API.
However, there might be a huge amount of A,
This will exceed the request time limit.
What's the best solution to solve this problem?
Thanks!!
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