Joins in sql not to consider for null in left outer join

Question

employee table containing empCode (fk), empName etc

role table containing roleCode (fk), roleName etc

employeeRoleMap table contains data of Many-To-Many of both (id, empCode, roleCode, isPrimaryRole etc)

One Employee can have many roles, among them only 1 primary role ( isPrimary = 1 )

To display employee details and primary role, I need to work on employee and employeeRoleMap table

So, query

select em.empCode, em.empName, em.roleCode
FROM employee em 
left join employeeRoleMap erm 
    on (em.empCode=erm.empCode AND erm.isPrimary=1) 

For which primary role is not there, it will show null. Okay.

But, now I want addition role details field like roleName.

So, I tried cross-join

select em.empCode, em.empName, em.roleCode
FROM employee em 
LEFT JOIN employeeRoleMap erm 
    on (em.empCode=erm.empCode AND erm.isPrimary=1) 
CROSS JOIN role r
WHERE em.roleCode = r.roleCode

It's working for who has roleCode, for employee having null as primary role code, those rows are getting ignored.

But, it shouldn't be the case right as employee is the left outer join even if rolecode is there or not, it should show

Answer 1

Instead of using CROSS JOIN , You can use LEFT JOIN

select em.empCode, em.empName, em.roleCode,r.RoleName
FROM employee em 
LEFT JOIN employeeRoleMap erm 
    on (em.empCode=erm.empCode AND erm.isPrimary=1) 
LEFT JOIN role r ON em.roleCode = r.roleCode

Answer 2

You could try

Select em.empCode, em.empName, em.roleCode
     FROM employee em 
 LEFT JOIN employeeRoleMap erm 
     on (em.empCode=erm.empCode AND erm.isPrimary=1) 
 LEFT JOIN role r
    on em.roleCode = r.roleCode

Without sample data it would be very difficult to know whether this would work or not.