SQL执行顺序

select distinct s.id
from S s
join T t on s.id=t.it
where t.name = "ranmou"
group by t.mobile
having count(*)>2
order by s.create_time
limit 5

执行顺序为：

1. from
2. join on
3. where
4. group by
5. having
6. select
7. distinct
8. order by 
9. limit