将Oracle分层查询转换为MySQL

Question

select to_char(
         (to_date(20160218, 'yyyymmdd') + (level - 1) / 24),
         'yyyymmddhh24'
       ) dt
from dual
connect by level <= 24

此SQL可以在Oracle中运行，但MySQL不支持这些分层函数（connect by level）。

如何将其翻译成MySQL？

Answer 1

您不一定需要递归查询才能生成24个值。您可以改为使用UNION ALL：

select '2016021800' as dt
union all
select '2016021801' as dt
union all
...
union all
select '2016021823' as dt;

变量日期也是如此，例如当前日期：

select date_format(curdate(), '%Y%m%d') || '01'
union all
select date_format(curdate(), '%Y%m%d') || '02'
union all
...
union all
select date_format(curdate(), '%Y%m%d') || '23';