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hive - HiveQL 基于日期的行、列之间的差异

问题描述

我有一个表（t_stocks），其中包含如下数据：

exchanged,stock_symbol,closing_date,closing_price
NSE,TCS,2009-08-09,2200.1
NSE,TCS,2009-08-10,2300.1
NSE,TCS,2009-08-11,12200.1
NSE,TCS,2009-08-12,22300.1
NSE,TCS,2009-09-09,2200.1
NSE,TCS,2009-09-10,2300.1
NSE,TCS,2009-09-11,12200.1
NSE,TCS,2009-09-12,22300.1
NSE,INFY,2009-08-09,2500.34
NSE,INFY,2009-08-10,1500.34
NSE,INFY,2009-08-09,7500.34
NSE,INFY,2009-08-10,14500.34
NSE,INFY,2009-09-09,2500.34
NSE,INFY,2009-09-10,1500.34
NSE,INFY,2009-09-09,7500.34
NSE,INFY,2009-09-10,14500.34
NSE,TCS,2010-08-09,2200.1
NSE,TCS,2010-08-10,2300.1
NSE,TCS,2010-08-11,12200.1
NSE,TCS,2010-08-12,22300.1
NSE,TCS,2010-09-09,2200.1
NSE,TCS,2010-09-10,2300.1
NSE,TCS,2010-09-11,12200.1
NSE,TCS,2010-09-12,22300.1
NSE,INFY,2010-08-09,2500.34
NSE,INFY,2010-08-10,1500.34
NSE,INFY,2010-08-09,7500.34
NSE,INFY,2010-08-10,14500.34
NSE,INFY,2010-09-09,2500.34
NSE,INFY,2010-09-10,1500.34
NSE,INFY,2010-09-09,7500.34
NSE,INFY,2010-09-10,14500.34
...
...

我需要编写一个生成如下报告的查询。交换， stock_symbol ， closing_date ， closing_price ，昨天_close ， diff_yesterday_price （昨天价格和今天价格之间的价格差异），输出如下：

+----------------+-------------------+-------------------+--------------------+------------------------+-----------------------+--+
| exchanged      |     stock_symbol  |     closing_date  |     closing_price  |     yesterday_closing  | diff_yesterday_price  |
+----------------+-------------------+-------------------+--------------------+------------------------+-----------------------+--+
| NSE            | INFY              | 2009-08-09        | 2500.34            | NULL                   | NULL                  |
| NSE            | INFY              | 2009-08-09        | 7500.34            | 2500.34                | -5000                 |
| NSE            | INFY              | 2009-08-10        | 14500.34           | 7500.34                | -7000                 |
| NSE            | INFY              | 2009-08-10        | 1500.34            | 14500.34               | 13000                 |
| NSE            | INFY              | 2009-09-09        | 7500.34            | 1500.34                | -6000                 |
| NSE            | INFY              | 2009-09-09        | 2500.34            | 7500.34                | 5000                  |
| NSE            | INFY              | 2009-09-10        | 14500.34           | 1500.34                | -13000                |
| NSE            | INFY              | 2009-09-10        | 1500.34            | 2500.34                | 1000                  |
| NSE            | INFY              | 2010-08-09        | 7500.34            | 14500.34               | 7000                  |
| NSE            | INFY              | 2010-08-09        | 2500.34            | 7500.34                | 5000                  |
.....
.....

任何人都可以给我一些线索以有效地做到这一点。

提前致谢，

问候。

标签： hivehiveql

解决方案

您可以使用蜂巢窗口功能lag()来解决这个问题。您可以在此处阅读有关 hive 中窗口函数的更多信息。

这是 中的有效演示，PostgreSQL但同样的查询也适用HIVE。

select
 exchanged,
 stock_symbol,
 closing_date,
 closing_price,
 yesterday_price,
 (yesterday_price - closing_price) as diff_yesterday_price
from
(
    select
        *,
        lag(closing_price) over (partition by stock_symbol order by closing_date) as yesterday_price
    from stockExchange
) la

order by
    stock_symbol,
    closing_date

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