day02-10 DQL语句总结

6、关于DQL语句的大总结：
select
…
from
…
where
…
group by
…
having
…
order by
…
limit
…

执行顺序？
	1.from
	2.where
	3.group by
	4.having
	5.select
	6.order by
	7.limit..