Question

我有一个表存储ID，用户，排名和CreatedDate。排名可以重复。我想将用户排名第4位，并获取排名1,2,3和4的最新20记录。

表格示例：

ID   User       Ranking     CreatedDate
----------------------------------------
1   B.Sisko       1st        1461136714  
2   B.Sisko       2nd        1461123378
3   B.Sisko       3rd        1461123378
4   B.Sisko       3rd        1461600137
5   K.Janeway     3rd        1461600137
6   K.Janeway     4th        1461602181
7   K.Janeway     4th        1461603096
8   J.Picard      3rd        1461603096
9   J.Picard      4th        1461603096
10  J.Picard      4th        1461603096

我想要的结果是：

ID   User       Ranking     CreatedDate
----------------------------------------
1   B.Sisko       1st        1461136714  
2   B.Sisko       2nd        1461123378
3   B.Sisko       3rd        1461123378
4   B.Sisko       3rd        1461600137
5   K.Janeway     3rd        1461600137
6   K.Janeway     4th        1461602181
7   J.Picard      3rd        1461603096
8   J.Picard      4th        1461603096

我想要一个能够检索它的查询。任何帮助将不胜感激。

Answer 1

如果没有某种第三方添加，您不能在SQL Server中使用LIMIT，但行号可能有用。

我不确定日期会发生什么，但这是一个想法：

WITH cte_1 AS(
SELECT MIN(DATE) AS DATE
  , USER
  , RANK
FROM TABLE
WHERE RANK = 4
GROUP BY USER, RANK
UNION ALL
SELECT DATE
  , USER
  , RANK
FROM TABLE
WHERE RANK <> 4
),
cte_2 AS (
SELECT *, ROW_NUMBER() OVER(ORDER BY USER, RANK) as run
FROM cte_1
)
SELECT *
FROM cte_2
WHERE rank <= 20

Answer 2

我想，你想要ORDER BY USER和RANK：

SELECT * FROM TABLE ORDER BY USER,RANK LIMIT 20

Answer 3

如果Ranking不等于4 或 Ranking为4，则以下查询将保留记录，但它最早为CreatedDate那个排名。

SELECT t1.*
FROM yourTable t1
LEFT JOIN
(
    SELECT Ranking, MIN(CreatedDate) AS CreatedDate
    FROM yourTable
    GROUP BY Ranking
) t2
    ON t1.Ranking = t2.Ranking AND t1.CreatedDate = t2.CreatedDate
WHERE t1.Ranking <> '4th' OR (t1.Ranking = '4th' AND t2.Ranking IS NOT NULL)

Answer 4

尚未确定您的问题，但请尝试关注;）

select *
from table1
where `Ranking` in ('1st', '2nd', '3rd', '4th')
group by
case `Ranking`
when '4th' then concat(`User`, `Ranking`)
else `ID` end
order by id

SQLFiddle demo here。

Answer 5

下面的代码可能很有用

;WITH CTE AS 
(
SELECT ROW_NUMBER()OVER(PARTITION BY [USER],RANKING ORDER BY Ranking,CreatedDate) as RN, * FROM #T
)
,CTE1 AS (
SELECT * from CTE WHERE Ranking IN ('1st','2nd','3rd')
)
SELECT ROW_NUMBER()OVER(ORDER BY ID) AS ID,[User]
, Ranking 
,CreatedDate
FROM(
SELECT ID,[User]
, Ranking 
,CreatedDate
FROM CTE1
UNION ALL
SELECT ID,[User]
, Ranking 
,CreatedDate
 FROM CTE 
WHERE RN =1 AND Ranking NOT IN ('1st','2nd','3rd')
) T

SQL查询检索最新的20条记录

5 个答案: