Try:
select e.name, w.rate, d.level
from employees e left join wage w on (e.job = w.job)
left join danger d on (d.job = e.job)
where d.level <= 2;
name rate level
---- ---- -----
sue -N- 1
alan 20 2
select e.name, w.rate, d.level
from employees e left join wage w on (e.job = w.job)
left join danger d on (d.job = e.job)
where d.level <= 2;
name rate level
---- ---- -----
sue -N- 1
alan 20 2
