完整的SQL

select 字段...
from 表名
where 条件
group by 分组字段...
having 分组后条件
order by 排序字段...
limit 索引，获取行数

SQL语句的执行顺序

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