Question

我有一个包含5列的表格，如下所示：

 | ID | NAME  | PO_NUMBER  | DATE       | STATS |
 | 1  | Jhon  | 160101-001 | 2016-01-01 | 7     |
 | 2  | Jhon  | 160101-002 | 2016-01-01 | 7     |
 | 3  | Jhon  | 160102-001 | 2016-01-02 | 7     |
 | 4  | Jane  | 160101-001 | 2016-01-01 | 7     |
 | 5  | Jane  | 160102-001 | 2016-01-02 | 7     |
 | 6  | Jane  | 160102-002 | 2016-01-02 | 7     |
 | 7  | Jane  | 160102-003 | 2016-01-02 | 7     |

我需要显示所有值，但stats字段没有重复，来自date字段喜欢这个

 | ID | NAME  | PO_NUMBER  | DATE       | STATS |
 | 1  | Jhon  | 160101-001 | 2016-01-01 | 7     |
 | 2  | Jhon  | 160101-002 | 2016-01-01 | null  |
 | 3  | Jhon  | 160102-001 | 2016-01-02 | 7     |
 | 4  | Jane  | 160101-001 | 2016-01-01 | 7     |
 | 5  | Jane  | 160102-001 | 2016-01-02 | 7     |
 | 6  | Jane  | 160102-002 | 2016-01-02 | null  |
 | 7  | Jane  | 160102-003 | 2016-01-02 | null  |

我遇到了希望的麻烦。感谢

Answer 1

从您的示例数据中，您似乎只想显示以stats结尾的po_number 001。如果是这样，这应该是最简单的方法：

select id, name, po_number, date, 
       case when right(po_number, 3) = '001' then stats else null end as stats
from yourtable

如果您想要order by po_number，那么这是使用row_number的一个选项：

select id, name, po_number, date, 
       case when rn = 1 then stats else null end as stats
from (
     select *, row_number() over (partition by name, date order by po_number) as rn
     from yourtable
) t

SQL Fiddle Demo

Answer 2

因为您使用的是SQL 2012，所以可以使用LEAD（）或LAG（）窗口函数来比较DATE值

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Answer 3

使用以下代码

  ;with temp as (
            select id,name ,PO_NUMBER ,DATE, STATS,
            LAG (STATS, 1, 0) 
            OVER (PARTITION BY name ,PO_NUMBER ,DATE ORDER BY id) AS PrevSTATS  
            from tableName 
    )
       select id,name ,PO_NUMBER ,DATE,
        case when  STATS = PrevSTATS then null 
               else     STATS end as STATS  
    from temp

如果在另一列SQL中值相同，则仅显示一条记录

3 个答案: