Question

我有包含与风险相关的数据的表格，我必须从风险表中获取最新和第二个最近的第二个数据

表格中的数据如下：

RiskID        RiskName     RiskScore       RiskDate    ItemID      
1             ABC            10          23/10/2013       12            
1             ABC            8           20/12/2013       12 
1             ABC            5           15/01/2014       12
2             BC             9           19/09/2013       12
2             BC             10          17/12/2013       12
2             BC             9           12/01/2014       12

我正在寻找下面的结果，其中ItemID应为12

R_ID   R_Name  Recent_R_Date  Recent_R_Score  Second_R_Date   Second_R_Date  ItemID
1       ABC       15/01/2014      5              20/12/2013       8           12
2       BC        12/01/2014      9             17/12/2013        10          12

Answer 1

修改

由于您已使用sql-server-2012标记，因此您可以访问LEAD和LAG分析函数，这样您就可以“查看”其他行。我还假设你需要'{分区'RiskName。

SELECT TOP 2 RiskId, RiskName, RiskDate AS Recent_R_Date, RiskScore AS Recent_R_Score, LAG(RiskDate) OVER (PARTITION BY RiskName ORDER BY RiskDate ASC) AS Second_R_Date, LAG(RiskScore) OVER (PARTITION BY RiskName ORDER BY RiskDate ASC) AS Second_R_Score, ItemID FROM Risk WHERE ItemID = 12 ORDER BY RiskDate DESC;

Fiddle here
<德尔> 它应该像按日期排序DESC一样简单，然后将结果限制为2，即：选择TOP 2 R_ID，R_Name，Recent_R_Date，Recent_R_Score， Second_R_Date，Second_R_Date，ItemID 来自风险 WHERE ItemID = 12 ORD BY RiskDate DESC;

Answer 2

一种方法（也适用于SQL Server 2008）

SELECT RiskID, RiskName,
       MAX(CASE WHEN rnum = 1 THEN RiskDate END) RecentDate,
       MAX(CASE WHEN rnum = 1 THEN RiskScore END) RecentScore,
       MAX(CASE WHEN rnum = 2 THEN RiskDate END) SecondDate,
       MAX(CASE WHEN rnum = 2 THEN RiskScore END) SecondScore,
       ItemID
  FROM
(
  SELECT *, ROW_NUMBER() OVER (PARTITION BY RiskID ORDER BY RiskDate DESC) rnum
    FROM Risk
   WHERE ItemID = 12
) q
 WHERE rnum <= 2
 GROUP BY ItemID, RiskID, RiskName
 ORDER BY RiskID

输出：

| RISKID | RISKNAME | RECENTDATE | RECENTSCORE | SECONDDATE | SECONDSCORE | ITEMID |
|--------|----------|------------|-------------|------------|-------------|--------|
|      1 |      ABC | 2014-01-15 |           5 | 2013-12-20 |           8 |     12 |
|      2 |       BC | 2014-01-12 |           9 | 2013-12-17 |          10 |     12 |

这是 SQLFiddle 演示

如何在SQL Server中获取最新和最近的值

2 个答案: