EJB 3 Problem: "Collections having FK in secondary table"

Question

Hi,
working with EJB 3 first time, i have to develop my entites by a DB scheme. It is very complex and now I have the problem using composite FK / PK in many tables, so that a refenrenced key has as the same time both properties: FK / PK.
Example: +3 Tables: Mxx:={M_ID as PK},
Lxx:={M_ID as PK / FK from Mxx},
Zxx:={M_ID as PK/FK from Lxx}+
I have built Mxx.java, Lxx.java with @EmbeddedId from LxxPK.java (works) and the problem table Zxx.java with @EmbeddedId from ZxxPK.java which includes a reference key and same time primary key from Lxx.
How can I solve the problem of "having FK in secondary table"?
THX for your help!

Answer 1

I will specify my problem a little more:
I have an Entity named zuordnung_module_lv_ma this references an Entity lehrveranstaltungen.
In zuordnung_module_lv_ma :
@OneToMany
@JoinColumn(...)
public Collection<lehrveranstaltungen> lv = new ArrayList...
For more detailed information look at this:
my only problem is the table zuordnung_module_lv_ma
SQL:
create table BLOECKE
BLOCKID integer not null,
WOCHENTAG integer,
ZEIT_VON datetime,
ZEIT_BIS datetime,
LOGISCHGELOESCHT char not null,
constraint PK_BLOECKE primary key (BLOCKID)
create table CURRICULA
CURRICULUMKUERZEL varchar not null,
CURRICULUMBEZ varchar,
CURRICULUMID integer not null,
IDVERANTWORTLICHERSTUDIENDEKAN integer,
LOGISCHEGELOESCHT char not null,
constraint PK_CURRICULA primary key (CURRICULUMID)
create table LEHRVERANSTALTUNGEN
MODUL_ID integer not null,
LV_ID integer not null,
SWS double not null,
ART_LV char not null,
LOGISCHGELOESCHT char not null,
MAXTEILNEHMER integer not null,
constraint PK_LEHRVERANSTALTUNGEN primary key (MODUL_ID, LV_ID, ART_LV)
create table MITARBEITER
MA_ID integer not null,
TITEL varchar,
NACHNAME varchar not null,
VORNAME varchar not null,
AUFGELAUFENESWS integer,
LETZTESFORSCHUNGSFREISEMESTER varchar,
BEGINNANSTELLUNG date,
ENDEANSTELLUNG date,
MA_KUERZEL varchar not null,
GEBURTSDATUM date,
LOGISCHGELOESCHT char not null,
MA_KATEGORIE_ID integer,
constraint PK_MITARBEITER primary key (MA_ID)
create table MITARBEITERKATEGORIE
MA_KATEGORIE_ID integer not null,
MA_KATEGORIE_BEZ varchar not null,
constraint PK_MITARBEITERKATEGORIE primary key (MA_KATEGORIE_ID)
create table MODULE
MODUL_ID integer not null,
MODULKUERZEL varchar not null,
IDMODULVERANTWORLTICHER integer not null,
IDSTVMODULVERANTWORTLICHER integer,
CURRICULUMID integer,
ID_MODULGRUPPE varchar,
MODULNAME varchar,
PFLICHTFACH binary,
SEMESTER integer,
CREDITPOINTS integer,
LOGISCHGELOESCHT char not null,
constraint PK_MODULE primary key (MODUL_ID)
create table MODULGRUPPEN
CURRICULUMID integer not null,
ID_MODULGRUPPE varchar not null,
MODULGRUPPENBEZ varchar,
LOGISCHGELOESCHT char not null,
constraint PK_MODULGRUPPEN primary key (CURRICULUMID, ID_MODULGRUPPE)
create table ZUORDNUNG_MODUL_CURRICULUM
MODUL_ID integer not null,
CURRICULUMID integer not null,
LOGISCHGELOESCHT char not null,
constraint PK_ZUORDNUNG_MODUL_CURRICULUM primary key (MODUL_ID, CURRICULUMID)
create table ZUORDNUNG_MODUL_LV_MA_SEMINAR_EXEMPLAR
MODUL_ID integer not null,
LV_ID integer not null,
ART_LV char not null,
SEMESTER varchar not null,
MA_ID integer not null,
WOCHE_G_U char not null,
BLOCKID integer not null,
EXEMPLAR varchar not null,
LOGISCHGELOESCHT char not null,
constraint PK_ZUORDNUNG_MODUL_LV_MA_SEMIN primary key (MODUL_ID, LV_ID, ART_LV, SEMESTER, MA_ID, WOCHE_G_U, BLOCKID, EXEMPLAR)
alter table CURRICULA
add constraint FK_CURRICUL_ZURODNUNG_MITARBEI foreign key (IDVERANTWORTLICHERSTUDIENDEKAN)
references MITARBEITER (MA_ID)
on update restrict
on delete restrict;
alter table LEHRVERANSTALTUNGEN
add constraint FK_LEHRVERA_ZURODNUNG_MODULE foreign key (MODUL_ID)
references MODULE (MODUL_ID)
on update restrict
on delete restrict;
alter table MITARBEITER
add constraint FK_MITARBEI_ZUORDNUNG_MITARBEI foreign key (MA_KATEGORIE_ID)
references MITARBEITERKATEGORIE (MA_KATEGORIE_ID)
on update restrict
on delete restrict;
alter table MODULE
add constraint FK_MODULE_ZUORDNUNG_MITARBEI foreign key (IDMODULVERANTWORLTICHER)
references MITARBEITER (MA_ID)
on update restrict
on delete restrict;
alter table MODULE
add constraint FK_MODULE_ZUORDNUNG_MODULGRU foreign key (CURRICULUMID, ID_MODULGRUPPE)
references MODULGRUPPEN (CURRICULUMID, ID_MODULGRUPPE)
on update restrict
on delete restrict;
alter table MODULGRUPPEN
add constraint FK_MODULGRU_ZUORDUNG__CURRICUL foreign key (CURRICULUMID)
references CURRICULA (CURRICULUMID)
on update restrict
on delete restrict;
alter table ZUORDNUNG_MODUL_CURRICULUM
add constraint FK_ZUORDNUN_ZUORDNUNG_CURRICUL foreign key (CURRICULUMID)
references CURRICULA (CURRICULUMID)
on update restrict
on delete restrict;
alter table ZUORDNUNG_MODUL_CURRICULUM
add constraint FK_ZUORDNUN_ZUORDNUNG_MODULE foreign key (MODUL_ID)
references MODULE (MODUL_ID)
on update restrict
on delete restrict;
alter table ZUORDNUNG_MODUL_LV_MA_SEMINAR_EXEMPLAR
add constraint FK_ZUORDNUN_ZUORDNUNG_BLOECKE foreign key (BLOCKID)
references BLOECKE (BLOCKID)
on update restrict
on delete restrict;
alter table ZUORDNUNG_MODUL_LV_MA_SEMINAR_EXEMPLAR
add constraint FK_ZUORDNUN_ZURODNUNG_LEHRVERA foreign key (MODUL_ID, LV_ID, ART_LV)
references LEHRVERANSTALTUNGEN (MODUL_ID, LV_ID, ART_LV)
on update restrict
on delete restrict;
alter table ZUORDNUNG_MODUL_LV_MA_SEMINAR_EXEMPLAR
add constraint FK_ZUORDNUN_ZURODNUNG_MITARBEI foreign key (MA_ID)
references MITARBEITER (MA_ID)
on update restrict
on delete restrict;
THX for prospective comments!