Lesson 03

select employee_id, last_name, department_id
from employees
where LOWER(last_name) = 'higgins';

select employee_id, concat ( first_name, last_name) Name,
      job_id, Length (last_name),
      instr (last_name, 'a') "Contains 'a'?"
from employees
where substr(job_id, 4 ) = 'REP';

select round (45.923,2), round(45.923,0),round(45.923,-1)
from dual;

select trunc(45.923,2),trunc(45.923),trunc(45.923,-1)
from dual;

select last_name, salary, mod(salary, 5000)
from employees
where job_id = 'SA_REP';

select last_name, hire_date
from employees
where hire_date < '01-FEB-88';

select sysdate
from dual;

select last_name, (sysdate-hire_date)/7 as Weeks
from employees
where department_id = 90;