[ADF BC] How to create an entity association to get one child

Question

I have two entities in a one-to-many relationship (say Employees and Employee_History). Each employee has one or more history entries.
What I would like to do is have an Employee view that contains all the attributes from the Employee entity and also an attribute (or many attributes) from the latest entry in the Employee_History entity.
Is there a way I can model this with ADF Business Components?
Things I've tried:
- adding SQL in the one-to-many association to ensure only one row is returned (does work, but affects other operations like creating a new employee record)
- creating a one-to-one association between the two entities (still returns more than one record)

Answer 1

Thank you Steve, that works great for the hire date, but what about when you need another column from the same record as that hire date.
Would you have to use a query like this?:
select DEPTNO, DNAME, LOC, (select max(firstname) from emp e where e.hiredate = (select max(hiredate) from emp where deptno = Dept.deptno) and e.deptno = Dept.depno)) as LAST_EMP_HIRED_NAME from dept DeptAt the moment I've been able to get it working like I want to (as far as I can tell) by referencing the child entity in the parent view and using a where clause in the view's SQL to reduce the rows returned, like this (using the example of departments and employees):
SELECT Dept.DEPTNO,
       Dept.DNAME,
       Dept.LOC,
       Emp.DEPTNO AS DEPTNO1,
       Emp.HIREDATE,
       Emp.FIRSTNAME
FROM DEPT Dept, EMP Emp
WHERE Dept.DEPTNO = Emp.DEPTNO AND Emp.HIREDATE = (SELECT MAX(HIREDATE) FROM EMP WHERE DEPTNO = Dept.DEPTNO)Testing this with the business components tester, it seems to work.