Question

我有两个表Add（父表）和AddXref（子表），并希望删除父表中的重复记录，并在Child表中更新。在AddXref表中，两个记录应该包含Add Table中的任何AddId.i尝试使用基本更新语句，但它没有工作。如何更新AddXref表？

我的尝试：到目前为止，我已经编写了查询，但我仍然坚持下一步做什么

Update AddXref name
SET a.AddId=b.AddId
FROM AddXref a
INNER JOIN Add b ON a.AddId = b.AddId
WHERE b.AddId = ( Select Top 1 ax.Addid from Add ax
                  INNER JOIN Add ax1  on
ax.AddressMain = a.AddressMain and
              ax.city = a.city and
              ax.Country = a.Country and
              ax.State = a.State and
              ax.ZipCode = a.ZipCode);

| AddId  | AddressMain  | City    | Country | State   | ZipCode    |
|--------|--------------|---------|---------|---------|------------|
| 8CA25D | 1234 Main St | Antioch | USA     | Florida | 60002-9714 |
| 5T7YTR | 1234 Main St | Antioch | USA     | Florida | 60002-9714 |

| AddXrefId | AddressId | IndividualId | InstitutionId |
|-----------|-----------|--------------|---------------|
| 822145    | 8CA25D    | 7652ER       | NULL          |
| 435902    | 5T7YTR    | NULL         | NA1043        |


| AddXrefId | AddressId | IndividualId | InstitutionId |
|-----------|-----------|--------------|---------------|
| 822145    | 8CA25D    | 7652ER       | NULL          |
| 435902    | 8CA25D    | NULL         | NA1043        | --Output either "8CA25D" or "5T7YTR" any one of it

Answer 1

首先收集重复数据。

select AddressMain, City, Country, State, ZipCode, min(addId) as minID, Max(addId) as MAxID
INTO #tmpData
from add
group by AddressMain, City, Country, State, ZipCode

第二次更新子表

Update AddXref 
SET a.AddId=b.MaxID
FROM AddXref a
INNER JOIN #tmpData b ON a.AddId = b.MinID -- you can use maxId too if you want.

第三个删除父母的重复记录。

DELETE FROM Add where AddId IN (Select MinID FROM #tmpData)

此代码未经过测试。

如何在SQL Server中更新和删除重复项？

1 个答案: