@Entity
@Table(name = "EVENT")
public class Event {

    //...
    
    @ManyToOne
    @JoinColumn(name = "EMLE_ID", nullable = true)
    private Employee employee;

    @ManyToOne
    @JoinColumn(name = "PNSM_ID", nullable = true)
    private ProtectionSystem protectionSystem;
    
    //...

select event from Event event where event.employee.department.id = :departmentId or event.protectionSystem.department.id = :departmentId

select event0_.EVNT_ID as EVNT1_75_, event0_.EVNT_CHANGE_DATE as EVNT2_75_, event0_.EVNT_CREATION_DATE as EVNT3_75_, event0_.EVNT_DATE as EVNT4_75_, event0_.DEVE_ID as DEVE5_75_, event0_.EMLE_ID as EMLE6_75_, event0_.ETTE_ID as ETTE7_75_, event0_.PNSM_ID as PNSM8_75_ from EVENT event0_, EMPLOYEE employee1_, PROTECTION_SYSTEM protection2_ where event0_.EMLE_ID=employee1_.EMLE_ID and event0_.PNSM_ID=protection2_.PNSM_ID and (employee1_.DERT_ID=? or protection2_.DERT_ID=?)