I was wondering if anybody had a good way to solve this... I have it semi-working, but the join columns are read only? is there anyway to get the join columns insertable/updateable?

Say I have 3 tables called TableA, TableB, TableC

Table A & Table B are basic 3 column composite primary key... Say id, globalId, and globalProfile.

table a(
id int not null,
global_id int not null,
global_profile varchar(50)
)

table b(
id int not null,
global_id int not null,
global_profile varchar(50)
)

TableC also has a 3 column composite primary key id, globalId, and globalProfile, however there's also foreign keys to table A & table B which reuse 2 of the 3 columns in the primary key for the foreign key to each table.

table c(
id int not null,
table_a_id int not null,
table_b_id int not null,
global_id int not null,
global_profile varchar(50)
)

so table c(table_a_id, global_id, global_profile) maps to table a(id, global_id, global_profile)

so table c(table_b_id, global_id, global_profile) maps to table b(id, global_id, global_profile)

I'm using....
@ManyToOne
@JoinColumns({
@JoinColumn(name="table_a_id", referencedColumnName="id",insertable=false, updatable=false),
@JoinColumn(name="global_id", referencedColumnName="global_id", insertable=false, updatable=false),
@JoinColumn(name="global_profile", referencedColumnName="global_profile", insertable=false, updatable=false)
})

@ManyToOne
@JoinColumns({
@JoinColumn(name="table_b_id", referencedColumnName="id", insertable=false, updatable=false),
@JoinColumn(name="global_id", referencedColumnName="global_id", insertable=false, updatable=false),
@JoinColumn(name="global_profile", referencedColumnName="global_profile", insertable=false, updatable=false)
})

So anybody have any good ways to create mutable data... if i remove the insertable/updatable i get an exception about mixing modes. if i remove it across all elements i get sorry can't repeat columns in definition or something...

I understand this is a highly abnormal configuration, but the application requirements require this type of configuration since it's highly distributed data, that's also synchronizable across to a central location, and it needs to be able to co-exist.

so anybody have any ideas on how best to make it have a mutable configuration settings? The other option is leave it read only .. . then anytime i need to mutate it just do that in straight jdbc??

Thanks for the ideas...

I have had a similar problem but I haven't found out a clean and official solution.

There is fortunately a dirty (for me) trick that works.

You can map a DB Column to more then one Entity property, so you can create, on Table C entity, 2 new properties like these:



When you modify these properties the modifications are propagated to DB.

Of course, in your code should be careful to keep the values synchronized between 2 properties which point to the same column on db.

I.e.
There will be a idTableA_1 (used as readonly property for join) and a idTableA_2.
When you alter idTableA_2 you must alter idTableA_1 with same value also