Hive 配置单元日期字符串验证
我正在尝试检查字符串是否为“YYYYMMDD”的有效日期格式 我正在使用下面的技术。但是对于无效的日期字符串,我得到的是有效的日期结果 我做错了什么Hive 配置单元日期字符串验证,hive,hql,unix-timestamp,Hive,Hql,Unix Timestamp,我正在尝试检查字符串是否为“YYYYMMDD”的有效日期格式 我正在使用下面的技术。但是对于无效的日期字符串,我得到的是有效的日期结果 我做错了什么 SELECT'20019999',CASE WHEN unix_timestamp('20019999','YYYYMMDD') > 0 THEN 'Good'ELSE 'Bad'END; 首先,您使用了错误的格式 select from_unixtime(unix_timestamp()) as de
SELECT'20019999',CASE WHEN unix_timestamp('20019999','YYYYMMDD') > 0 THEN 'Good'ELSE 'Bad'END;
首先,您使用了错误的格式
select from_unixtime(unix_timestamp()) as default_format
,from_unixtime(unix_timestamp(),'YYYY-MM-DD') as wrong_format
,from_unixtime(unix_timestamp(),'yyyy-MM-dd') as right_format
;
其次,没有对日期部件范围进行验证。
如果您将日数部分增加1,则它会将您转发到第二天
with t as (select stack(7,'27','28','29','30','31','32','33') as dy)
select t.dy
,from_unixtime(unix_timestamp(concat('2017-02-',t.dy),'yyyy-MM-dd'),'yyyy-MM-dd') as dt
from t
;
如果您将月份部分增加1,则它会将您转发到下一个月
with t as (select stack(5,'10','11','12','13','14') as mn)
select t.mn
,from_unixtime(unix_timestamp(concat('2017-',t.mn,'-01'),'yyyy-MM-dd'),'yyyy-MM-dd') as dt
from t
;
即使使用CAST,验证也只在零件范围内进行,而不是在日期本身
select cast('2010-02-32' as date);
这里有一个实现目标的方法:
with t as (select '20019999' as dt)
select dt
,from_unixtime(unix_timestamp(dt,'yyyyMMdd'),'yyyyMMdd') as double_converted_dt
,case
when from_unixtime(unix_timestamp(dt,'yyyyMMdd'),'yyyyMMdd') = dt
then 'Good'
else 'Bad'
end as dt_status
from t
;
@jenesaisquoi,伟大的:-)
+-----+-------------+
| mn | dt |
+-----+-------------+
| 10 | 2017-10-01 |
| 11 | 2017-11-01 |
| 12 | 2017-12-01 |
| 13 | 2018-01-01 |
| 14 | 2018-02-01 |
+-----+-------------+
select cast('2010-02-32' as date);
+-------+
| _c0 |
+-------+
| NULL |
+-------+
select cast('2010-02-29' as date);
+-------------+
| _c0 |
+-------------+
| 2010-03-01 |
+-------------+
with t as (select '20019999' as dt)
select dt
,from_unixtime(unix_timestamp(dt,'yyyyMMdd'),'yyyyMMdd') as double_converted_dt
,case
when from_unixtime(unix_timestamp(dt,'yyyyMMdd'),'yyyyMMdd') = dt
then 'Good'
else 'Bad'
end as dt_status
from t
;
+-----------+----------------------+------------+
| dt | double_converted_dt | dt_status |
+-----------+----------------------+------------+
| 20019999 | 20090607 | Bad |
+-----------+----------------------+------------+