Unidirectional one-to-many with join table

Question

According to http://docs.jboss.org/hibernate/orm/3.5/reference/en-US/html/associations.html#assoc-unidirectional-12m "A unidirectional one-to-many association on a foreign key is an unusual case, and is not recommended", instead they recommend using a join table, e.g.
create table Person ( personId bigint not null primary key )
create table PersonAddress ( personId not null, addressId bigint not null primary key )
create table Address ( addressId bigint not null primary key )
However if doing this, when using SQLDeveloper the Address table does not appear as a child table of Person, which it should be as a unidirectional one-to-many meaning that I can't create a cache group for Person and subsequently Person.
Is this something that can be worked around as I'm using a legacy schema created from Hibernate/JPA and the implications of changing are quite substantial?
Thanks

Answer 1

Hi Gennady,
Apologies but my question was not clear enough. The schema structure that I have inherited is as follows:
CREATE TABLE T_PERSON ( PERSONID NUMBER PRIMARY KEY, PERSONFIRSTNAME VARCHAR2(20), PERSONLASTNAME VARCHAR2(20) );
CREATE TABLE T_PERSONADDRESS (PERSONID NUMBER NOT NULL, ADDRESSID NUMBER NOT NULL PRIMARY KEY );
CREATE TABLE T_ADDRESS ( ADDRESSID NUMBER  PRIMARY KEY, ADDRESSTEXT VARCHAR2(200) );
ALTER TABLE T_PERSONADDRESS ADD CONSTRAINT FK_PERSON_ADDR_PERSON_ID FOREIGN KEY (PERSONID) REFERENCES T_PERSON(PERSONID);
ALTER TABLE T_PERSONADDRESS ADD CONSTRAINT FK_PERSON_ADDR_ADDR_ID FOREIGN KEY (ADDRESSID) REFERENCES T_ADDRESS(ADDRESSID);This is implementing a unidirectional one-to-many relationship between T_PERSON and T_ADDRESS according to the Hibernate and JPA recommendation. As far as I can see most schema designers would do this using by adding a column "PERSON_ID" (and associated FK) on the T_ADDRESS table and therefore not needing the T_PERSONADDRESS table.
This being what it is, I would then like to create a cache-group as follows:
CREATE READONLY CACHE GROUP "CACHEGROUPADDRESSES"
AUTOREFRESH MODE INCREMENTAL INTERVAL 5 MINUTES
STATE PAUSED
FROM
  "SCHEMA1"."T_PERSON" (
    "PERSONID"        NUMBER            NOT NULL,
    "PERSONFIRSTNAME" VARCHAR2(20 BYTE),
    "PERSONLASTNAME"  VARCHAR2(20 BYTE),
    PRIMARY KEY("PERSONID")
  "SCHEMA1"."T_ADDRESS" (
    "ADDRESSID" NUMBER NOT NULL,
    "ADDRESSTEXT" VARCHAR2(20 BYTE),
    PRIMARY KEY("ADDRESSID")
  "SCHEMA1"."T_PERSONADDRESS" (
    "PERSONID"  NUMBER NOT NULL,
    "ADDRESSID" NUMBER NOT NULL,
    PRIMARY KEY("ADDRESSID"),
    FOREIGN KEY("PERSONID")
      REFERENCES "SCHEMA1"."T_PERSON"("PERSONID"),
    FOREIGN KEY("ADDRESSID")
      REFERENCES "SCHEMA1"."T_ADDRESS"("ADDRESSID")
  )This however gives me the error "TT8222: Multiple parent tables found" because TimesTen has failed to identify the one-to-many-using-link-table pattern.
Without a schema re-write is there anything that I can do, alternatively will this be looked at for a future release of TimesTen?
Edited by: TrisStev on Apr 16, 2012 10:37 AM