我有一个组织的SQL Server数据库，有许多重复的行。我想运行一个选择语句来获取所有这些和被欺骗的数量，同时还返回与每个组织相关的id。
这样的陈述:
SELECT orgName, COUNT(*) AS dupes
FROM organizations
GROUP BY orgName
HAVING (COUNT(*) > 1)
将返回如下内容
orgName | dupes
ABC Corp | 7
Foo Federation | 5
Widget Company | 2
但我也想要他们的id。有什么办法可以做到吗?也许就像
orgName | dupeCount | id
ABC Corp | 1 | 34
ABC Corp | 2 | 5
...
Widget Company | 1 | 10
Widget Company | 2 | 2
原因是还有一个单独的用户表链接到这些组织，我想把它们统一起来(因此删除dupes，用户链接到同一个组织，而不是dupe组织)。但我想手动部分，所以我不会搞砸任何事情，但我仍然需要一个语句返回所有的dupe组织的id，这样我就可以通过用户列表。
我想我知道你需要什么
我需要混合各种答案，我认为我得到了他想要的解决方案:
select o.id,o.orgName, oc.dupeCount, oc.id,oc.orgName
from organizations o
inner join (
SELECT MAX(id) as id, orgName, COUNT(*) AS dupeCount
FROM organizations
GROUP BY orgName
HAVING COUNT(*) > 1
) oc on o.orgName = oc.orgName
有了Max id，你就会得到副本的id和他要求的原件的id:
id org name , dublicate count (missing out in this case)
id doublicate org name , doub count (missing out again because does not help in this case)
唯一可悲的是你把它写成了这种形式
id , name , dubid , name
希望它仍然有用
有几种方法可以选择重复的行。
对于我的解决方案，首先考虑以下表格为例
CREATE TABLE #Employee
(
ID INT,
FIRST_NAME NVARCHAR(100),
LAST_NAME NVARCHAR(300)
)
INSERT INTO #Employee VALUES ( 1, 'Ardalan', 'Shahgholi' );
INSERT INTO #Employee VALUES ( 2, 'name1', 'lname1' );
INSERT INTO #Employee VALUES ( 3, 'name2', 'lname2' );
INSERT INTO #Employee VALUES ( 2, 'name1', 'lname1' );
INSERT INTO #Employee VALUES ( 3, 'name2', 'lname2' );
INSERT INTO #Employee VALUES ( 4, 'name3', 'lname3' );
第一个解决方案:
SELECT DISTINCT *
FROM #Employee;
WITH #DeleteEmployee AS (
SELECT ROW_NUMBER()
OVER(PARTITION BY ID, First_Name, Last_Name ORDER BY ID) AS
RNUM
FROM #Employee
)
SELECT *
FROM #DeleteEmployee
WHERE RNUM > 1
SELECT DISTINCT *
FROM #Employee
第二个解决方案:使用标识字段
SELECT DISTINCT *
FROM #Employee;
ALTER TABLE #Employee ADD UNIQ_ID INT IDENTITY(1, 1)
SELECT *
FROM #Employee
WHERE UNIQ_ID < (
SELECT MAX(UNIQ_ID)
FROM #Employee a2
WHERE #Employee.ID = a2.ID
AND #Employee.FIRST_NAME = a2.FIRST_NAME
AND #Employee.LAST_NAME = a2.LAST_NAME
)
ALTER TABLE #Employee DROP COLUMN UNIQ_ID
SELECT DISTINCT *
FROM #Employee
所有解决方案的最后使用这个命令
DROP TABLE #Employee
你可以这样做:
SELECT
o.id, o.orgName, d.intCount
FROM (
SELECT orgName, COUNT(*) as intCount
FROM organizations
GROUP BY orgName
HAVING COUNT(*) > 1
) AS d
INNER JOIN organizations o ON o.orgName = d.orgName
如果你只想返回可以删除的记录(每个记录只留下一个)，你可以使用:
SELECT
id, orgName
FROM (
SELECT
orgName, id,
ROW_NUMBER() OVER (PARTITION BY orgName ORDER BY id) AS intRow
FROM organizations
) AS d
WHERE intRow != 1
编辑:SQL Server 2000没有ROW_NUMBER()函数。相反，你可以使用:
SELECT
o.id, o.orgName, d.intCount
FROM (
SELECT orgName, COUNT(*) as intCount, MIN(id) AS minId
FROM organizations
GROUP BY orgName
HAVING COUNT(*) > 1
) AS d
INNER JOIN organizations o ON o.orgName = d.orgName
WHERE d.minId != o.id
