Question

我想批量更新同一个表中的某些行。我有一个表，比方说TABLEA，有Id列和OriginalID。我想编写一个内部联接与其他表的组合的查询：

Update TABLEA 
SET OriginalID = Id 
FROM TABLEA A
INNER JOIN TableB B ON <join condition>
INNER JOIN TableC C ON <join condition>
WHERE c.SomeCol = <value>

这适用于SQL Server 2005和Oracle，它提供了错误

SQL错误：ORA-00933：SQL命令未正确结束。

Answer 1

其他解决方案：

可更新的观点：

UPDATE (SELECT OriginalID, ID FROM TABLEA A 
INNER JOIN TableB B ON <join condition> 
INNER JOIN TableC C ON <join condition> 
WHERE c.SomeCol = <value> 
)  
SET OriginalID = Id;

您也可以使用MERGE语句。

MERGE INTO TableA USING
(SELECT <used columns, ids> 
FROM TableB B
INNER JOIN TableC C ON <join condition> 
WHERE c.SomeCol = <value>)
ON (<join condition beteen A and B>)
WHEN MATCHED THEN 
UPDATE SET
OriginalID = ID;

Answer 2

我相信你想要这样的东西。

UPDATE tableA a
   SET OriginalID = (SELECT a2.id
                       FROM tableA a2 
                            JOIN tableB b ON (<<join between a,b,and a2>>)
                            JOIN tableC c ON (<<join between b,and c>>)
                      WHERE c.SomeCol = <<value>>)
 WHERE EXISTS( SELECT 1
                 FROM tableA a2 
                      JOIN tableB b ON (<<join between a,b,and a2>>)
                      JOIN tableC c ON (<<join between b,and c>>)
                WHERE c.SomeCol = <<value>>)

在Oracle中使用自联接批量更新

2 个答案: