我有一个用sqoop获取数据的表，每天它都会被截断。
开头的这个tabsqoop有这些值:
+----+-------+--------------+---------------+---------+--------+
| id | names | created_date | modified_date | country | number |
+----+-------+--------------+---------------+---------+--------+
| 33 | nick | 1/1/2020 | 1/1/2020 | Dubai | 1234 |
| 45 | ted | 2/7/2020 | 2/7/2020 | Spain | 12345 |
+----+-------+--------------+---------------+---------+--------+
并插入到tblmax .
第二天tblSqoop有这个数据:
+----+-------+--------------+---------------+---------+--------+
| id | names | created_date | modified_date | country | number |
+----+-------+--------------+---------------+---------+--------+
| 33 | nick | 1/1/2020 | 12/31/2020 | Dubai | 1234 |
| 45 | ted | 2/7/2020 | 8/19/2020 | Spain | 12345 |
| 45 | ted | 2/7/2020 | 9/12/2020 | Spain | 12345 |
| 45 | ted | 2/7/2020 | 10/11/2020 | Spain | 12346 |
| 45 | ted | 2/7/2020 | 1/1/2021 | Spain | 12345 |
+----+-------+--------------+---------------+---------+--------+
我想要的是在tblmax里面有最新的信息，比如:
+----+-------+--------------+---------------+---------+--------------------+
| id | names | created_date | modified_date | country | number |status_date|
+----+-------+--------------+---------------+---------+--------+-----------+
| 33 | nick | 1/1/2020 | 12/31/2020 | Dubai | 1234 |12/31/2020 |
| 45 | ted | 2/7/2020 | 10/11/2020 | Spain | 12346 |10/11/2020 |
| 45 | ted | 2/7/2020 | 1/1/2021 | Spain | 12345 |1/1/2021 |
+----+-------+--------------+---------------+---------+--------+-----------+
我正在运行这个:
insert into tblMaxed
select
id,
names,
created_date,
modified_date,
country,
number,
MAX(modified_date) as status_date
from tblSqoop
group by id,
names,
created_date,
modified_date,
country,
number
但结果我把所有的记录都拿了一遍。会有助于PK的使用吗?
能否截断表并使用此重新加载tblMaxed?(说明在代码中)
select
id,
names,
created_date,
modified_date,
country,
number,
modified_date as status_date
FROM
(select t.*, row_number() OVER (PARTITION BY id,number Order by id,number , modified_date desc) rn from tblSqoop t) rs
where rs.rn=1 -- This will pick up data for MAX modified_date from sqoop table