Question

我有以下sql查询

SELECT m.School, c.avgscore 
FROM postswithratings c 
join ZEntrycriteria on c.fk_postID= m.schoolcode

提供以下结果

School| avgscore
xyz   |  5
xyz   |  5
xyz   |  5
abc   |  3
abc   |  3
kkk   |  1

我的问题是如何删除这些副本并仅获取跟踪。

 School| avgscore
    xyz   |  5 
    abc   |  3
    kkk   |  1

我试过

   SELECT m.School, c.avgscore 
   FROM postswithratings c 
   join ZEntrycriteria on c.fk_postID= m.schoolcode 
   group by m.School

但它给了我以下错误

＆＃34;专栏＆posts ;withwithratings.avgscore＆＃39;在选择列表中无效因为它不包含在聚合函数或 GROUP BY子句。＆＃34;

Answer 1

无需复杂化。请跟：

SELECT m.School, c.avgscore 
FROM postswithratings c 
join ZEntrycriteria on c.fk_postID= m.schoolcode 
group by m.School, c.avgscore

或

SELECT DISTINCT m.School, c.avgscore 
FROM postswithratings c 
join ZEntrycriteria on c.fk_postID= m.schoolcode

Answer 2

您只需添加如下所示的不同关键字： -

filebeat2017/04/19 06:54:22.450440 beat.go:339: CRIT Exiting: error loading config file: stat filebeat.yml: no such file or directory
Exiting: error loading config file: stat filebeat.yml: no such file or directory

Answer 3

这将删除重复行（仅重复）

<强>架构：

CREATE TABLE #TAB (School varchar(5) , avgscore int)
INSERT INTO #TAB
SELECT 'xyz', 5
UNION ALL
SELECT 'xyz', 5
UNION ALL
SELECT 'xyz', 5
UNION ALL
SELECT 'abc', 3
UNION ALL
SELECT 'abc', 3
UNION ALL
SELECT 'kkk', 1

现在使用CTE作为您的Tempprary View并删除数据。

;WITH CTE AS(
SELECT ROW_NUMBER() OVER (PARTITION BY School,avgscore  ORDER BY (SELECT 1)) DUP_C, 
School,  avgscore FROM #TAB
)

DELETE FROM CTE WHERE DUP_C>1

现在检查#TAB，数据将是

+--------+----------+
| School | avgscore |
+--------+----------+
| xyz    |        5 |
| abc    |        3 |
| kkk    |        1 |
+--------+----------+

Answer 4

CREATE TABLE #Table2
    ([School] varchar(3), [avgscore] int)

INSERT INTO #Table2
    ([School], [avgscore])
VALUES
    ('xyz', 5),
    ('xyz', 5),
    ('xyz', 5),
    ('abc', 3),
    ('abc', 3),
    ('kkk', 1)
;
SELECT  SCHOOL,AVGSCORE FROM (SELECT *,ROW_NUMBER() OVER( PARTITION BY [AVGSCORE] ORDER BY (SELECT NULL)) AS RN FROM #TABLE2)A
WHERE RN=1
ORDER BY AVGSCORE
-------
;WITH CTE AS
(SELECT *,ROW_NUMBER() OVER( PARTITION BY [AVGSCORE] ORDER BY (SELECT NULL)) AS RN FROM #TABLE2)
SELECT SCHOOL,AVGSCORE  FROM CTE WHERE RN=1

输出

SCHOOL  AVGSCORE
kkk      1
abc      3
xyz      5

Answer 5

使用DISTINCT关键字将使sql使用集而不是多集。所以值只出现一次

Answer 6

如果您正在使用聚合函数，则只使用group by，例如。最大。总之，平均

在那种情况下，

SELECT Distinct(m.School), c.avgscore 
FROM postswithratings c 
join ZEntrycriteria on c.fk_postID= m.schoolcode

从已连接的表

6 个答案: