hibernate question ?

[tomo]

Let's say i have table A, and table B that are in a m:n relationship with
table C thas hold's their id's.
And then I save one record in table A that is linked to two records in table
B, through table C.Now I
don't want that link anymore, i wan't to delete 2 rows in table C that are
holding this info. Is this
possible without deleting records from table a and table b ?



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[Jean-Baptiste Nizet]

Let's say i have table A, and table B that are in a m:n relationship with
table C thas hold's their id's.
And then I save one record in table A that is linked to two records in table
B, through table C.Now I
don't want that link anymore, i wan't to delete 2 rows in table C that are
holding this info. Is this
possible without deleting records from table a and table b ?

Of course :

@Entity
public class A {
// ...
private Set<B> bs = new HashSet<B>();

public void removeBs() {
bs.clear();
}
}

Be careful that, if your relationship is bidirectional, both sides of
the relationship should be maintained and stay coherent, which can be
tricky and can lead to infinite loops if badly done.

@Entity
public class A {
// ...
private Set<B> bs = new HashSet<B>();

public void removeBs() {
for (B b : bs) {
b.removeA(this);
}
bs.clear();
}
}

 

[Lew]

Let's say i have table A, and table B that are in a m:n relationship with
table C thas hold's their id's.
And then I save one record in table A that is linked to two records in table
B, through table C.Now I
don't want that link anymore, i wan't to delete 2 rows in table C that are
holding this info. Is this
possible without deleting records from table a and table b ?

It's certainly possible in the database itself.