sql - How to write a trigger to move data I want to delete from a table to antother before deleting it -

i wrote trigger monitor table called employees , , when deleting employee table trigger should fire , , copy employee want delete table employees , put in table called deleted_employees , when put following sql statement delete employees employee_id = 100 sql error says :

error starting @ line 17 in command: delete employees employee_id = 100 error report: sql error: ora-02292: integrity constraint (hr.dept_mgr_fk) violated - child                       record found 02292. 00000 - "integrity constraint (%s.%s) violated - child record found" *cause:    attempted delete parent key value had foreign            dependency. *action:   delete dependencies first parent or disable constraint.  create or replace trigger employee_deleted    before delete on employees  declare   cursor cur_emp     select  employee_id , first_name , last_name , email ,              phone_number , hire_date , job_id , salary ,             commission_pct ,  manager_id , department_id       employees;   emp_rec cur_emp%rowtype; begin   open cur_emp;    while(cur_emp%found) loop     fetch cur_emp emp_rec;     insert  deleted_employees       (employee_id , first_name , last_name ,        email ,        phone_number , hire_date ,job_id , salary ,        commission_pct ,  manager_id , department_id)     values       (emp_rec.employee_id ,emp_rec.first_name ,emp_rec.last_name ,        emp_rec.email , emp_rec.phone_number , emp_rec.hire_date ,        emp_rec.job_id , emp_rec.salary , emp_rec.commission_pct ,        emp_rec.manager_id , emp_rec.department_id);   end loop;    close cur_emp; end; 

i don't know how test trigger , ideas ?!

one thing observed are, mistake, inserting records employee table deleted_employees.

i think want insert employee detail deleted_employee table in delete action.

for in oracle can using :old keyword refer current running record. if want delete related chile records .. can in trigger without problem -

create or replace trigger employee_deleted  before delete on employees  each row declare begin insert  deleted_employees (  employee_id , first_name , last_name , email ,  phone_number , hire_date ,job_id , salary ,  commission_pct ,  manager_id , department_id ) values (:old.employee_id ,:old.first_name ,:old.last_name , :old.email ,  :old.phone_number , :old.hire_date , :old.job_id , :old.salary ,  :old.commission_pct ,  :old.manager_id , :old.department_id);  delete department employee_id = :old.employee_id; -- if deleting child record not ora:02292 error  end; 

just edit delete part in trigger per database.

for need first check key constraint dept_mgr_fk. guessed key present in department table on employee_id column.

so check key , change second last line , compile.