应该为此编写什么查询？

Question

您好，我有一笔银行客户的交易 table。 table 的名称是 CUST_TRANSACTION。它有几个字段，如 CUST_ID、TRANSACTION_DATE 等。我想编写一个查询，以便我可以 select 3 个特定客户 ID 的最后一笔交易。例如

TRANSACTION_ID | CUST_ID | TRANSACTION_DATE | TRANSACTION_DESC

100023 | 2 | 15-12-2014 06:00 | Withdraw 1000 dollars
100022 | 5 | 14-12-2014 16:00 | Deposit 1000 dollars 
100021 | 5 | 14-12-2014 15:00 | Withdraw 500 dollars
100020 | 4 | 12-12-2014 15:00 | Withdraw 300 dollars
100019 | 4 | 12-12-2014 14:39 | Deposit 300 dollars
100018 | 2 | 12-12-2014 15:00 | Withdraw 60 dollars

我想获取 ID 为 2、4、5 的最后一笔交易

TRANSACTION_ID | CUST_ID | TRANSACTION_DATE | TRANSACTION_DESC

100023 | 2 | 15-12-2014 06:00 | Withdraw 1000 dollars
100022 | 5 | 14-12-2014 16:00 | Deposit 1000 dollars
100020 | 4 | 12-12-2014 15:00 | Withdraw 300 dollars

我该如何处理？

编辑：到目前为止我已经试过了

select * 
from CUST_TRANSACTION 
where CUST_ID IN('2', '5', '4') 
and rownum <4 
order by transaction_date desc

Answer 1

试试这个

select t1.TRANSACTION_ID , 
t1.CUST_ID ,t1.TRANSACTION_DATE ,t1.TRANSACTION_DESC from table t1 
inner join
(
select CUST_ID ,min(TRANSACTION_DATE) as  TRANSACTION_DATE from table
group by CUST_ID
) t2
on t1.CUST_ID=t2.CUST_ID and t1.TRANSACTION_DATE =t2.TRANSACTION_DATE

Answer 2

根据客户 ID 分组并获得最大值 (transaction_date)。获取包含此客户 ID 和 transaction_date 组合

的记录

Answer 3

你应该试试这个

SELECT CUST_ID , a.TRANSACTION_ID, TRANSACTION_DATE , TRANSACTION_DESC from CUST_TRANSACTION AS a
INNER JOIN (SELECT MAX(TRANSACTION_ID) TRANSACTION_ID FROM CUST_TRANSACTION GROUP BY CUST_ID) AS b ON a.TRANSACTION_ID=b.TRANSACTION_ID

Answer 4

使用 rank() 获取最高项，然后 select 仅获取每个项的最高行。例如：

SELECT *
FROM (
  select 
    transaction_id,
    cust_id,
    transaction_date,
    transaction_desc,
    rank() OVER (PARTITION BY cust_id ORDER BY cust_id, transaction_date desc) AS rank_id
  from cust_transaction
  ) ct
WHERE ct.rank_id = 1

见SQL Fiddle。

应该为此编写什么查询？

What query should be written for this?

sql

oracle

greatest-n-per-group