我有一个有帐号和卡号的数据库。我将这些匹配到一个文件,以将任何卡号更新为帐号,这样我只使用帐号。

我创建了一个将表链接到帐户/卡数据库的视图,以返回table ID和相关的帐号,现在我需要更新那些ID与account number匹配的记录。

这是Sales_Import表,其中的帐号字段需要更新:

LeadID AccountNumber
147 5807811235
150 5807811326
185 7006100100007267039

这是RetrieveAccountNumber表,我需要从这里更新:

LeadID AccountNumber
147 7006100100007266957
150 7006100100007267039

我尝试了下面的方法,但到目前为止运气都不佳:

UPDATE [Sales_Lead].[dbo].[Sales_Import] 
SET    [AccountNumber] = (SELECT RetrieveAccountNumber.AccountNumber 
                          FROM   RetrieveAccountNumber 
                          WHERE  [Sales_Lead].[dbo].[Sales_Import]. LeadID = 
                                                RetrieveAccountNumber.LeadID) 

它将卡号更新为帐号,但是帐号被NULL替换


当前回答

对于MySql工作良好:

UPDATE
    Sales_Import SI,RetrieveAccountNumber RAN
SET
    SI.AccountNumber = RAN.AccountNumber
WHERE
    SI.LeadID = RAN.LeadID

其他回答

甲骨文

use

UPDATE suppliers
SET supplier_name = (SELECT customers.customer_name
                     FROM customers
                     WHERE customers.customer_id = suppliers.supplier_id)
WHERE EXISTS (SELECT customers.customer_name
              FROM customers
              WHERE customers.customer_id = suppliers.supplier_id);

对于MySql工作良好:

UPDATE
    Sales_Import SI,RetrieveAccountNumber RAN
SET
    SI.AccountNumber = RAN.AccountNumber
WHERE
    SI.LeadID = RAN.LeadID

总结其他答案,关于如何仅在“匹配存在”时使用来自另一个表的数据更新目标表,有4种变体

查询和子查询:

update si
set    si.AccountNumber = (
    select ran.AccountNumber 
    from   RetrieveAccountNumber ran
    where  si.LeadID = ran.LeadID
)
from Sales_Import si
where exists (select * from RetrieveAccountNumber ran where ran.LeadID = si.LeadID)

内连接:

update si
set si.AccountNumber = ran.AccountNumber
from Sales_Import si inner join RetrieveAccountNumber ran on si.LeadID = ran.LeadID

交叉连接:

update si
set si.AccountNumber = ran.AccountNumber
from Sales_Import si, RetrieveAccountNumber ran
where si.LeadID = ran.LeadID

走:

merge into Sales_Import si
using RetrieveAccountNumber ran on si.LeadID = ran.LeadID 
when matched then update set si.accountnumber = ran.accountnumber;

所有的变体都是更少的琐碎和可以理解的,我个人更喜欢“内部连接”选项。但其中任何一种都可以使用,开发者必须根据自己的需求选择“更好的选项”

从性能的角度来看,使用join的变体更可取:

MYSQL(这是我最喜欢的恢复所有特定列reasonId值的方法,基于主键id等价)

UPDATE `site` AS destination  
INNER JOIN `site_copy` AS backupOnTuesday 
      ON backupOnTuesday.`id` = destination.`id`
SET destdestination.`reasonId` = backupOnTuesday.`reasonId`

将内容从一个表复制到另一个表的简单方法如下:

UPDATE table2 
SET table2.col1 = table1.col1, 
table2.col2 = table1.col2,
...
FROM table1, table2 
WHERE table1.memberid = table2.memberid

还可以添加条件以复制特定的数据。