drop table emp_table purge
/
drop table job_table purge
/
create table job_table(
                       job_id number,
                       min_salary number
                      )
/
alter table job_table
  add constraint job_table_pk
    primary key(job_id)
/
create table emp_table(
                       employee_id number,
                       name varchar2(10),
                       job_id number,
                       salary number
                      )
/
alter table emp_table
  add constraint emp_table_pk
    primary key(employee_id)
/
alter table emp_table
  add constraint emp_table_fk1
    foreign key(job_id)
    references job_table
/
create or replace
  trigger job_table_bur
    before update
    on job_table
    for each row
    begin
        if :old.min_salary != :new.min_salary or :old.job_id != :new.job_id
          then
            update emp_table
               set salary = greatest(salary,:new.min_salary),
                   job_id = :new.job_id
             where job_id = :old.job_id;
        end if;
end;
/
insert
  into job_table
  values(
         1,
         30000
        )
/
insert
  into job_table
  values(
         2,
         40000
        )
/
insert
  into emp_table
  values(
         1,
         'Vasya',
         1,
         30000
        )
/
insert
  into emp_table
  values(
         2,
         'Petya',
         1,
         30000
        )
/
insert
  into emp_table
  values(
         3,
         'Misha',
         1,
         40000
        )
/
insert
  into emp_table
  values(
         4,
         'Sasha',
         2,
         40000
        )
/
insert
  into emp_table
  values(
         5,
         'Masha',
         2,
         40000
        )
/
insert
  into emp_table
  values(
         6,
         'Dasha',
         2,
         45000
        )
/
commit
/

Commit complete.

SQL> select  *
  2    from  emp_table
  3  /

EMPLOYEE_ID NAME           JOB_ID     SALARY
----------- ---------- ---------- ----------
          1 Vasya               1      30000
          2 Petya               1      30000
          3 Misha               1      40000
          4 Sasha               2      40000
          5 Masha               2      40000
          6 Dasha               2      45000

6 rows selected.

SQL> select  *
  2    from  job_table
  3  /

    JOB_ID MIN_SALARY
---------- ----------
         1      30000
         2      40000

SQL> update job_table
  2     set min_salary = min_salary + 5000,
  3         job_id = job_id + 10
  4  /

2 rows updated.

SQL> select  *
  2    from  emp_table
  3  /

EMPLOYEE_ID NAME           JOB_ID     SALARY
----------- ---------- ---------- ----------
          1 Vasya              11      35000
          2 Petya              11      35000
          3 Misha              11      40000
          4 Sasha              12      45000
          5 Masha              12      45000
          6 Dasha              12      45000

6 rows selected.

SQL> select  *
  2    from  job_table
  3  /

    JOB_ID MIN_SALARY
---------- ----------
        11      35000
        12      45000

SQL>

create or replace
  trigger job_table_bur
    before update
    on job_table
    for each row
    begin
        if :old.min_salary != :new.min_salary
          then
            update emp_table
               set salary = :new.min_salary
             where job_id = :new.job_id
               and salary < :new.min_salary;
        end if;
end;
/